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-rw-r--r--activerecord/lib/arel/alias_predication.rb9
-rw-r--r--activerecord/lib/arel/attributes.rb22
-rw-r--r--activerecord/lib/arel/attributes/attribute.rb37
-rw-r--r--activerecord/lib/arel/collectors/bind.rb24
-rw-r--r--activerecord/lib/arel/collectors/composite.rb31
-rw-r--r--activerecord/lib/arel/collectors/plain_string.rb20
-rw-r--r--activerecord/lib/arel/collectors/sql_string.rb20
-rw-r--r--activerecord/lib/arel/collectors/substitute_binds.rb28
-rw-r--r--activerecord/lib/arel/compatibility/wheres.rb35
-rw-r--r--activerecord/lib/arel/crud.rb42
-rw-r--r--activerecord/lib/arel/delete_manager.rb18
-rw-r--r--activerecord/lib/arel/errors.rb9
-rw-r--r--activerecord/lib/arel/expressions.rb29
-rw-r--r--activerecord/lib/arel/factory_methods.rb49
-rw-r--r--activerecord/lib/arel/insert_manager.rb49
-rw-r--r--activerecord/lib/arel/math.rb45
-rw-r--r--activerecord/lib/arel/nodes.rb67
-rw-r--r--activerecord/lib/arel/nodes/and.rb32
-rw-r--r--activerecord/lib/arel/nodes/ascending.rb23
-rw-r--r--activerecord/lib/arel/nodes/binary.rb52
-rw-r--r--activerecord/lib/arel/nodes/bind_param.rb32
-rw-r--r--activerecord/lib/arel/nodes/case.rb55
-rw-r--r--activerecord/lib/arel/nodes/casted.rb46
-rw-r--r--activerecord/lib/arel/nodes/count.rb12
-rw-r--r--activerecord/lib/arel/nodes/delete_statement.rb45
-rw-r--r--activerecord/lib/arel/nodes/descending.rb23
-rw-r--r--activerecord/lib/arel/nodes/equality.rb18
-rw-r--r--activerecord/lib/arel/nodes/extract.rb24
-rw-r--r--activerecord/lib/arel/nodes/false.rb16
-rw-r--r--activerecord/lib/arel/nodes/full_outer_join.rb8
-rw-r--r--activerecord/lib/arel/nodes/function.rb44
-rw-r--r--activerecord/lib/arel/nodes/grouping.rb8
-rw-r--r--activerecord/lib/arel/nodes/in.rb8
-rw-r--r--activerecord/lib/arel/nodes/infix_operation.rb80
-rw-r--r--activerecord/lib/arel/nodes/inner_join.rb8
-rw-r--r--activerecord/lib/arel/nodes/insert_statement.rb37
-rw-r--r--activerecord/lib/arel/nodes/join_source.rb20
-rw-r--r--activerecord/lib/arel/nodes/matches.rb18
-rw-r--r--activerecord/lib/arel/nodes/named_function.rb23
-rw-r--r--activerecord/lib/arel/nodes/node.rb50
-rw-r--r--activerecord/lib/arel/nodes/node_expression.rb13
-rw-r--r--activerecord/lib/arel/nodes/outer_join.rb8
-rw-r--r--activerecord/lib/arel/nodes/over.rb15
-rw-r--r--activerecord/lib/arel/nodes/regexp.rb16
-rw-r--r--activerecord/lib/arel/nodes/right_outer_join.rb8
-rw-r--r--activerecord/lib/arel/nodes/select_core.rb63
-rw-r--r--activerecord/lib/arel/nodes/select_statement.rb41
-rw-r--r--activerecord/lib/arel/nodes/sql_literal.rb16
-rw-r--r--activerecord/lib/arel/nodes/string_join.rb11
-rw-r--r--activerecord/lib/arel/nodes/table_alias.rb27
-rw-r--r--activerecord/lib/arel/nodes/terminal.rb16
-rw-r--r--activerecord/lib/arel/nodes/true.rb16
-rw-r--r--activerecord/lib/arel/nodes/unary.rb44
-rw-r--r--activerecord/lib/arel/nodes/unary_operation.rb20
-rw-r--r--activerecord/lib/arel/nodes/unqualified_column.rb22
-rw-r--r--activerecord/lib/arel/nodes/update_statement.rb41
-rw-r--r--activerecord/lib/arel/nodes/values.rb16
-rw-r--r--activerecord/lib/arel/nodes/values_list.rb24
-rw-r--r--activerecord/lib/arel/nodes/window.rb126
-rw-r--r--activerecord/lib/arel/nodes/with.rb11
-rw-r--r--activerecord/lib/arel/order_predications.rb13
-rw-r--r--activerecord/lib/arel/predications.rb249
-rw-r--r--activerecord/lib/arel/select_manager.rb271
-rw-r--r--activerecord/lib/arel/table.rb110
-rw-r--r--activerecord/lib/arel/tree_manager.rb72
-rw-r--r--activerecord/lib/arel/update_manager.rb34
-rw-r--r--activerecord/lib/arel/visitors.rb20
-rw-r--r--activerecord/lib/arel/visitors/depth_first.rb199
-rw-r--r--activerecord/lib/arel/visitors/dot.rb292
-rw-r--r--activerecord/lib/arel/visitors/ibm_db.rb21
-rw-r--r--activerecord/lib/arel/visitors/informix.rb55
-rw-r--r--activerecord/lib/arel/visitors/mssql.rb143
-rw-r--r--activerecord/lib/arel/visitors/mysql.rb83
-rw-r--r--activerecord/lib/arel/visitors/oracle.rb159
-rw-r--r--activerecord/lib/arel/visitors/oracle12.rb67
-rw-r--r--activerecord/lib/arel/visitors/postgresql.rb116
-rw-r--r--activerecord/lib/arel/visitors/sqlite.rb39
-rw-r--r--activerecord/lib/arel/visitors/to_sql.rb911
-rw-r--r--activerecord/lib/arel/visitors/visitor.rb42
-rw-r--r--activerecord/lib/arel/visitors/where_sql.rb23
-rw-r--r--activerecord/lib/arel/window_predications.rb9
81 files changed, 4698 insertions, 0 deletions
diff --git a/activerecord/lib/arel/alias_predication.rb b/activerecord/lib/arel/alias_predication.rb
new file mode 100644
index 0000000000..4abbbb7ef6
--- /dev/null
+++ b/activerecord/lib/arel/alias_predication.rb
@@ -0,0 +1,9 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module AliasPredication
+ def as(other)
+ Nodes::As.new self, Nodes::SqlLiteral.new(other)
+ end
+ end
+end
diff --git a/activerecord/lib/arel/attributes.rb b/activerecord/lib/arel/attributes.rb
new file mode 100644
index 0000000000..35d586c948
--- /dev/null
+++ b/activerecord/lib/arel/attributes.rb
@@ -0,0 +1,22 @@
+# frozen_string_literal: true
+
+require "arel/attributes/attribute"
+
+module Arel # :nodoc: all
+ module Attributes
+ ###
+ # Factory method to wrap a raw database +column+ to an Arel Attribute.
+ def self.for(column)
+ case column.type
+ when :string, :text, :binary then String
+ when :integer then Integer
+ when :float then Float
+ when :decimal then Decimal
+ when :date, :datetime, :timestamp, :time then Time
+ when :boolean then Boolean
+ else
+ Undefined
+ end
+ end
+ end
+end
diff --git a/activerecord/lib/arel/attributes/attribute.rb b/activerecord/lib/arel/attributes/attribute.rb
new file mode 100644
index 0000000000..ecf499a23e
--- /dev/null
+++ b/activerecord/lib/arel/attributes/attribute.rb
@@ -0,0 +1,37 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module Attributes
+ class Attribute < Struct.new :relation, :name
+ include Arel::Expressions
+ include Arel::Predications
+ include Arel::AliasPredication
+ include Arel::OrderPredications
+ include Arel::Math
+
+ ###
+ # Create a node for lowering this attribute
+ def lower
+ relation.lower self
+ end
+
+ def type_cast_for_database(value)
+ relation.type_cast_for_database(name, value)
+ end
+
+ def able_to_type_cast?
+ relation.able_to_type_cast?
+ end
+ end
+
+ class String < Attribute; end
+ class Time < Attribute; end
+ class Boolean < Attribute; end
+ class Decimal < Attribute; end
+ class Float < Attribute; end
+ class Integer < Attribute; end
+ class Undefined < Attribute; end
+ end
+
+ Attribute = Attributes::Attribute
+end
diff --git a/activerecord/lib/arel/collectors/bind.rb b/activerecord/lib/arel/collectors/bind.rb
new file mode 100644
index 0000000000..6f8912575d
--- /dev/null
+++ b/activerecord/lib/arel/collectors/bind.rb
@@ -0,0 +1,24 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module Collectors
+ class Bind
+ def initialize
+ @binds = []
+ end
+
+ def <<(str)
+ self
+ end
+
+ def add_bind(bind)
+ @binds << bind
+ self
+ end
+
+ def value
+ @binds
+ end
+ end
+ end
+end
diff --git a/activerecord/lib/arel/collectors/composite.rb b/activerecord/lib/arel/collectors/composite.rb
new file mode 100644
index 0000000000..0533544993
--- /dev/null
+++ b/activerecord/lib/arel/collectors/composite.rb
@@ -0,0 +1,31 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module Collectors
+ class Composite
+ def initialize(left, right)
+ @left = left
+ @right = right
+ end
+
+ def <<(str)
+ left << str
+ right << str
+ self
+ end
+
+ def add_bind(bind, &block)
+ left.add_bind bind, &block
+ right.add_bind bind, &block
+ self
+ end
+
+ def value
+ [left.value, right.value]
+ end
+
+ private
+ attr_reader :left, :right
+ end
+ end
+end
diff --git a/activerecord/lib/arel/collectors/plain_string.rb b/activerecord/lib/arel/collectors/plain_string.rb
new file mode 100644
index 0000000000..c0e9fff399
--- /dev/null
+++ b/activerecord/lib/arel/collectors/plain_string.rb
@@ -0,0 +1,20 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module Collectors
+ class PlainString
+ def initialize
+ @str = +""
+ end
+
+ def value
+ @str
+ end
+
+ def <<(str)
+ @str << str
+ self
+ end
+ end
+ end
+end
diff --git a/activerecord/lib/arel/collectors/sql_string.rb b/activerecord/lib/arel/collectors/sql_string.rb
new file mode 100644
index 0000000000..54e1e562c2
--- /dev/null
+++ b/activerecord/lib/arel/collectors/sql_string.rb
@@ -0,0 +1,20 @@
+# frozen_string_literal: true
+
+require "arel/collectors/plain_string"
+
+module Arel # :nodoc: all
+ module Collectors
+ class SQLString < PlainString
+ def initialize(*)
+ super
+ @bind_index = 1
+ end
+
+ def add_bind(bind)
+ self << yield(@bind_index)
+ @bind_index += 1
+ self
+ end
+ end
+ end
+end
diff --git a/activerecord/lib/arel/collectors/substitute_binds.rb b/activerecord/lib/arel/collectors/substitute_binds.rb
new file mode 100644
index 0000000000..4b894bc4b1
--- /dev/null
+++ b/activerecord/lib/arel/collectors/substitute_binds.rb
@@ -0,0 +1,28 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module Collectors
+ class SubstituteBinds
+ def initialize(quoter, delegate_collector)
+ @quoter = quoter
+ @delegate = delegate_collector
+ end
+
+ def <<(str)
+ delegate << str
+ self
+ end
+
+ def add_bind(bind)
+ self << quoter.quote(bind)
+ end
+
+ def value
+ delegate.value
+ end
+
+ private
+ attr_reader :quoter, :delegate
+ end
+ end
+end
diff --git a/activerecord/lib/arel/compatibility/wheres.rb b/activerecord/lib/arel/compatibility/wheres.rb
new file mode 100644
index 0000000000..c8a73f0dae
--- /dev/null
+++ b/activerecord/lib/arel/compatibility/wheres.rb
@@ -0,0 +1,35 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module Compatibility # :nodoc:
+ class Wheres # :nodoc:
+ include Enumerable
+
+ module Value # :nodoc:
+ attr_accessor :visitor
+ def value
+ visitor.accept self
+ end
+
+ def name
+ super.to_sym
+ end
+ end
+
+ def initialize(engine, collection)
+ @engine = engine
+ @collection = collection
+ end
+
+ def each
+ to_sql = Visitors::ToSql.new @engine
+
+ @collection.each { |c|
+ c.extend(Value)
+ c.visitor = to_sql
+ yield c
+ }
+ end
+ end
+ end
+end
diff --git a/activerecord/lib/arel/crud.rb b/activerecord/lib/arel/crud.rb
new file mode 100644
index 0000000000..e8a563ca4a
--- /dev/null
+++ b/activerecord/lib/arel/crud.rb
@@ -0,0 +1,42 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ ###
+ # FIXME hopefully we can remove this
+ module Crud
+ def compile_update(values, pk)
+ um = UpdateManager.new
+
+ if Nodes::SqlLiteral === values
+ relation = @ctx.from
+ else
+ relation = values.first.first.relation
+ end
+ um.key = pk
+ um.table relation
+ um.set values
+ um.take @ast.limit.expr if @ast.limit
+ um.order(*@ast.orders)
+ um.wheres = @ctx.wheres
+ um
+ end
+
+ def compile_insert(values)
+ im = create_insert
+ im.insert values
+ im
+ end
+
+ def create_insert
+ InsertManager.new
+ end
+
+ def compile_delete
+ dm = DeleteManager.new
+ dm.take @ast.limit.expr if @ast.limit
+ dm.wheres = @ctx.wheres
+ dm.from @ctx.froms
+ dm
+ end
+ end
+end
diff --git a/activerecord/lib/arel/delete_manager.rb b/activerecord/lib/arel/delete_manager.rb
new file mode 100644
index 0000000000..fdba937d64
--- /dev/null
+++ b/activerecord/lib/arel/delete_manager.rb
@@ -0,0 +1,18 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ class DeleteManager < Arel::TreeManager
+ include TreeManager::StatementMethods
+
+ def initialize
+ super
+ @ast = Nodes::DeleteStatement.new
+ @ctx = @ast
+ end
+
+ def from(relation)
+ @ast.relation = relation
+ self
+ end
+ end
+end
diff --git a/activerecord/lib/arel/errors.rb b/activerecord/lib/arel/errors.rb
new file mode 100644
index 0000000000..2f8d5e3c02
--- /dev/null
+++ b/activerecord/lib/arel/errors.rb
@@ -0,0 +1,9 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ class ArelError < StandardError
+ end
+
+ class EmptyJoinError < ArelError
+ end
+end
diff --git a/activerecord/lib/arel/expressions.rb b/activerecord/lib/arel/expressions.rb
new file mode 100644
index 0000000000..da8afb338c
--- /dev/null
+++ b/activerecord/lib/arel/expressions.rb
@@ -0,0 +1,29 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module Expressions
+ def count(distinct = false)
+ Nodes::Count.new [self], distinct
+ end
+
+ def sum
+ Nodes::Sum.new [self]
+ end
+
+ def maximum
+ Nodes::Max.new [self]
+ end
+
+ def minimum
+ Nodes::Min.new [self]
+ end
+
+ def average
+ Nodes::Avg.new [self]
+ end
+
+ def extract(field)
+ Nodes::Extract.new [self], field
+ end
+ end
+end
diff --git a/activerecord/lib/arel/factory_methods.rb b/activerecord/lib/arel/factory_methods.rb
new file mode 100644
index 0000000000..83ec23e403
--- /dev/null
+++ b/activerecord/lib/arel/factory_methods.rb
@@ -0,0 +1,49 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ ###
+ # Methods for creating various nodes
+ module FactoryMethods
+ def create_true
+ Arel::Nodes::True.new
+ end
+
+ def create_false
+ Arel::Nodes::False.new
+ end
+
+ def create_table_alias(relation, name)
+ Nodes::TableAlias.new(relation, name)
+ end
+
+ def create_join(to, constraint = nil, klass = Nodes::InnerJoin)
+ klass.new(to, constraint)
+ end
+
+ def create_string_join(to)
+ create_join to, nil, Nodes::StringJoin
+ end
+
+ def create_and(clauses)
+ Nodes::And.new clauses
+ end
+
+ def create_on(expr)
+ Nodes::On.new expr
+ end
+
+ def grouping(expr)
+ Nodes::Grouping.new expr
+ end
+
+ ###
+ # Create a LOWER() function
+ def lower(column)
+ Nodes::NamedFunction.new "LOWER", [Nodes.build_quoted(column)]
+ end
+
+ def coalesce(*exprs)
+ Nodes::NamedFunction.new "COALESCE", exprs
+ end
+ end
+end
diff --git a/activerecord/lib/arel/insert_manager.rb b/activerecord/lib/arel/insert_manager.rb
new file mode 100644
index 0000000000..c90fc33a48
--- /dev/null
+++ b/activerecord/lib/arel/insert_manager.rb
@@ -0,0 +1,49 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ class InsertManager < Arel::TreeManager
+ def initialize
+ super
+ @ast = Nodes::InsertStatement.new
+ end
+
+ def into(table)
+ @ast.relation = table
+ self
+ end
+
+ def columns; @ast.columns end
+ def values=(val); @ast.values = val; end
+
+ def select(select)
+ @ast.select = select
+ end
+
+ def insert(fields)
+ return if fields.empty?
+
+ if String === fields
+ @ast.values = Nodes::SqlLiteral.new(fields)
+ else
+ @ast.relation ||= fields.first.first.relation
+
+ values = []
+
+ fields.each do |column, value|
+ @ast.columns << column
+ values << value
+ end
+ @ast.values = create_values values, @ast.columns
+ end
+ self
+ end
+
+ def create_values(values, columns)
+ Nodes::Values.new values, columns
+ end
+
+ def create_values_list(rows)
+ Nodes::ValuesList.new(rows)
+ end
+ end
+end
diff --git a/activerecord/lib/arel/math.rb b/activerecord/lib/arel/math.rb
new file mode 100644
index 0000000000..2359f13148
--- /dev/null
+++ b/activerecord/lib/arel/math.rb
@@ -0,0 +1,45 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module Math
+ def *(other)
+ Arel::Nodes::Multiplication.new(self, other)
+ end
+
+ def +(other)
+ Arel::Nodes::Grouping.new(Arel::Nodes::Addition.new(self, other))
+ end
+
+ def -(other)
+ Arel::Nodes::Grouping.new(Arel::Nodes::Subtraction.new(self, other))
+ end
+
+ def /(other)
+ Arel::Nodes::Division.new(self, other)
+ end
+
+ def &(other)
+ Arel::Nodes::Grouping.new(Arel::Nodes::BitwiseAnd.new(self, other))
+ end
+
+ def |(other)
+ Arel::Nodes::Grouping.new(Arel::Nodes::BitwiseOr.new(self, other))
+ end
+
+ def ^(other)
+ Arel::Nodes::Grouping.new(Arel::Nodes::BitwiseXor.new(self, other))
+ end
+
+ def <<(other)
+ Arel::Nodes::Grouping.new(Arel::Nodes::BitwiseShiftLeft.new(self, other))
+ end
+
+ def >>(other)
+ Arel::Nodes::Grouping.new(Arel::Nodes::BitwiseShiftRight.new(self, other))
+ end
+
+ def ~@
+ Arel::Nodes::BitwiseNot.new(self)
+ end
+ end
+end
diff --git a/activerecord/lib/arel/nodes.rb b/activerecord/lib/arel/nodes.rb
new file mode 100644
index 0000000000..5af0e532e2
--- /dev/null
+++ b/activerecord/lib/arel/nodes.rb
@@ -0,0 +1,67 @@
+# frozen_string_literal: true
+
+# node
+require "arel/nodes/node"
+require "arel/nodes/node_expression"
+require "arel/nodes/select_statement"
+require "arel/nodes/select_core"
+require "arel/nodes/insert_statement"
+require "arel/nodes/update_statement"
+require "arel/nodes/bind_param"
+
+# terminal
+
+require "arel/nodes/terminal"
+require "arel/nodes/true"
+require "arel/nodes/false"
+
+# unary
+require "arel/nodes/unary"
+require "arel/nodes/grouping"
+require "arel/nodes/ascending"
+require "arel/nodes/descending"
+require "arel/nodes/unqualified_column"
+require "arel/nodes/with"
+
+# binary
+require "arel/nodes/binary"
+require "arel/nodes/equality"
+require "arel/nodes/in" # Why is this subclassed from equality?
+require "arel/nodes/join_source"
+require "arel/nodes/delete_statement"
+require "arel/nodes/table_alias"
+require "arel/nodes/infix_operation"
+require "arel/nodes/unary_operation"
+require "arel/nodes/over"
+require "arel/nodes/matches"
+require "arel/nodes/regexp"
+
+# nary
+require "arel/nodes/and"
+
+# function
+# FIXME: Function + Alias can be rewritten as a Function and Alias node.
+# We should make Function a Unary node and deprecate the use of "aliaz"
+require "arel/nodes/function"
+require "arel/nodes/count"
+require "arel/nodes/extract"
+require "arel/nodes/values"
+require "arel/nodes/values_list"
+require "arel/nodes/named_function"
+
+# windows
+require "arel/nodes/window"
+
+# conditional expressions
+require "arel/nodes/case"
+
+# joins
+require "arel/nodes/full_outer_join"
+require "arel/nodes/inner_join"
+require "arel/nodes/outer_join"
+require "arel/nodes/right_outer_join"
+require "arel/nodes/string_join"
+
+require "arel/nodes/sql_literal"
+
+require "arel/nodes/casted"
diff --git a/activerecord/lib/arel/nodes/and.rb b/activerecord/lib/arel/nodes/and.rb
new file mode 100644
index 0000000000..c530a77bfb
--- /dev/null
+++ b/activerecord/lib/arel/nodes/and.rb
@@ -0,0 +1,32 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module Nodes
+ class And < Arel::Nodes::Node
+ attr_reader :children
+
+ def initialize(children)
+ super()
+ @children = children
+ end
+
+ def left
+ children.first
+ end
+
+ def right
+ children[1]
+ end
+
+ def hash
+ children.hash
+ end
+
+ def eql?(other)
+ self.class == other.class &&
+ self.children == other.children
+ end
+ alias :== :eql?
+ end
+ end
+end
diff --git a/activerecord/lib/arel/nodes/ascending.rb b/activerecord/lib/arel/nodes/ascending.rb
new file mode 100644
index 0000000000..8b617f4df5
--- /dev/null
+++ b/activerecord/lib/arel/nodes/ascending.rb
@@ -0,0 +1,23 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module Nodes
+ class Ascending < Ordering
+ def reverse
+ Descending.new(expr)
+ end
+
+ def direction
+ :asc
+ end
+
+ def ascending?
+ true
+ end
+
+ def descending?
+ false
+ end
+ end
+ end
+end
diff --git a/activerecord/lib/arel/nodes/binary.rb b/activerecord/lib/arel/nodes/binary.rb
new file mode 100644
index 0000000000..e184e99c73
--- /dev/null
+++ b/activerecord/lib/arel/nodes/binary.rb
@@ -0,0 +1,52 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module Nodes
+ class Binary < Arel::Nodes::NodeExpression
+ attr_accessor :left, :right
+
+ def initialize(left, right)
+ super()
+ @left = left
+ @right = right
+ end
+
+ def initialize_copy(other)
+ super
+ @left = @left.clone if @left
+ @right = @right.clone if @right
+ end
+
+ def hash
+ [self.class, @left, @right].hash
+ end
+
+ def eql?(other)
+ self.class == other.class &&
+ self.left == other.left &&
+ self.right == other.right
+ end
+ alias :== :eql?
+ end
+
+ %w{
+ As
+ Assignment
+ Between
+ GreaterThan
+ GreaterThanOrEqual
+ Join
+ LessThan
+ LessThanOrEqual
+ NotEqual
+ NotIn
+ Or
+ Union
+ UnionAll
+ Intersect
+ Except
+ }.each do |name|
+ const_set name, Class.new(Binary)
+ end
+ end
+end
diff --git a/activerecord/lib/arel/nodes/bind_param.rb b/activerecord/lib/arel/nodes/bind_param.rb
new file mode 100644
index 0000000000..ba8340558a
--- /dev/null
+++ b/activerecord/lib/arel/nodes/bind_param.rb
@@ -0,0 +1,32 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module Nodes
+ class BindParam < Node
+ attr_reader :value
+
+ def initialize(value)
+ @value = value
+ super()
+ end
+
+ def hash
+ [self.class, self.value].hash
+ end
+
+ def eql?(other)
+ other.is_a?(BindParam) &&
+ value == other.value
+ end
+ alias :== :eql?
+
+ def nil?
+ value.nil?
+ end
+
+ def boundable?
+ !value.respond_to?(:boundable?) || value.boundable?
+ end
+ end
+ end
+end
diff --git a/activerecord/lib/arel/nodes/case.rb b/activerecord/lib/arel/nodes/case.rb
new file mode 100644
index 0000000000..654a54825e
--- /dev/null
+++ b/activerecord/lib/arel/nodes/case.rb
@@ -0,0 +1,55 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module Nodes
+ class Case < Arel::Nodes::Node
+ attr_accessor :case, :conditions, :default
+
+ def initialize(expression = nil, default = nil)
+ @case = expression
+ @conditions = []
+ @default = default
+ end
+
+ def when(condition, expression = nil)
+ @conditions << When.new(Nodes.build_quoted(condition), expression)
+ self
+ end
+
+ def then(expression)
+ @conditions.last.right = Nodes.build_quoted(expression)
+ self
+ end
+
+ def else(expression)
+ @default = Else.new Nodes.build_quoted(expression)
+ self
+ end
+
+ def initialize_copy(other)
+ super
+ @case = @case.clone if @case
+ @conditions = @conditions.map { |x| x.clone }
+ @default = @default.clone if @default
+ end
+
+ def hash
+ [@case, @conditions, @default].hash
+ end
+
+ def eql?(other)
+ self.class == other.class &&
+ self.case == other.case &&
+ self.conditions == other.conditions &&
+ self.default == other.default
+ end
+ alias :== :eql?
+ end
+
+ class When < Binary # :nodoc:
+ end
+
+ class Else < Unary # :nodoc:
+ end
+ end
+end
diff --git a/activerecord/lib/arel/nodes/casted.rb b/activerecord/lib/arel/nodes/casted.rb
new file mode 100644
index 0000000000..c1e6e97d6d
--- /dev/null
+++ b/activerecord/lib/arel/nodes/casted.rb
@@ -0,0 +1,46 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module Nodes
+ class Casted < Arel::Nodes::NodeExpression # :nodoc:
+ attr_reader :val, :attribute
+ def initialize(val, attribute)
+ @val = val
+ @attribute = attribute
+ super()
+ end
+
+ def nil?; @val.nil?; end
+
+ def hash
+ [self.class, val, attribute].hash
+ end
+
+ def eql?(other)
+ self.class == other.class &&
+ self.val == other.val &&
+ self.attribute == other.attribute
+ end
+ alias :== :eql?
+ end
+
+ class Quoted < Arel::Nodes::Unary # :nodoc:
+ alias :val :value
+ def nil?; val.nil?; end
+ end
+
+ def self.build_quoted(other, attribute = nil)
+ case other
+ when Arel::Nodes::Node, Arel::Attributes::Attribute, Arel::Table, Arel::Nodes::BindParam, Arel::SelectManager, Arel::Nodes::Quoted, Arel::Nodes::SqlLiteral
+ other
+ else
+ case attribute
+ when Arel::Attributes::Attribute
+ Casted.new other, attribute
+ else
+ Quoted.new other
+ end
+ end
+ end
+ end
+end
diff --git a/activerecord/lib/arel/nodes/count.rb b/activerecord/lib/arel/nodes/count.rb
new file mode 100644
index 0000000000..880464639d
--- /dev/null
+++ b/activerecord/lib/arel/nodes/count.rb
@@ -0,0 +1,12 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module Nodes
+ class Count < Arel::Nodes::Function
+ def initialize(expr, distinct = false, aliaz = nil)
+ super(expr, aliaz)
+ @distinct = distinct
+ end
+ end
+ end
+end
diff --git a/activerecord/lib/arel/nodes/delete_statement.rb b/activerecord/lib/arel/nodes/delete_statement.rb
new file mode 100644
index 0000000000..a419975335
--- /dev/null
+++ b/activerecord/lib/arel/nodes/delete_statement.rb
@@ -0,0 +1,45 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module Nodes
+ class DeleteStatement < Arel::Nodes::Node
+ attr_accessor :left, :right, :orders, :limit, :offset, :key
+
+ alias :relation :left
+ alias :relation= :left=
+ alias :wheres :right
+ alias :wheres= :right=
+
+ def initialize(relation = nil, wheres = [])
+ super()
+ @left = relation
+ @right = wheres
+ @orders = []
+ @limit = nil
+ @offset = nil
+ @key = nil
+ end
+
+ def initialize_copy(other)
+ super
+ @left = @left.clone if @left
+ @right = @right.clone if @right
+ end
+
+ def hash
+ [self.class, @left, @right, @orders, @limit, @offset, @key].hash
+ end
+
+ def eql?(other)
+ self.class == other.class &&
+ self.left == other.left &&
+ self.right == other.right &&
+ self.orders == other.orders &&
+ self.limit == other.limit &&
+ self.offset == other.offset &&
+ self.key == other.key
+ end
+ alias :== :eql?
+ end
+ end
+end
diff --git a/activerecord/lib/arel/nodes/descending.rb b/activerecord/lib/arel/nodes/descending.rb
new file mode 100644
index 0000000000..f3f6992ca8
--- /dev/null
+++ b/activerecord/lib/arel/nodes/descending.rb
@@ -0,0 +1,23 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module Nodes
+ class Descending < Ordering
+ def reverse
+ Ascending.new(expr)
+ end
+
+ def direction
+ :desc
+ end
+
+ def ascending?
+ false
+ end
+
+ def descending?
+ true
+ end
+ end
+ end
+end
diff --git a/activerecord/lib/arel/nodes/equality.rb b/activerecord/lib/arel/nodes/equality.rb
new file mode 100644
index 0000000000..551d56c2ff
--- /dev/null
+++ b/activerecord/lib/arel/nodes/equality.rb
@@ -0,0 +1,18 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module Nodes
+ class Equality < Arel::Nodes::Binary
+ def operator; :== end
+ alias :operand1 :left
+ alias :operand2 :right
+ end
+
+ %w{
+ IsDistinctFrom
+ IsNotDistinctFrom
+ }.each do |name|
+ const_set name, Class.new(Equality)
+ end
+ end
+end
diff --git a/activerecord/lib/arel/nodes/extract.rb b/activerecord/lib/arel/nodes/extract.rb
new file mode 100644
index 0000000000..5799ee9b8f
--- /dev/null
+++ b/activerecord/lib/arel/nodes/extract.rb
@@ -0,0 +1,24 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module Nodes
+ class Extract < Arel::Nodes::Unary
+ attr_accessor :field
+
+ def initialize(expr, field)
+ super(expr)
+ @field = field
+ end
+
+ def hash
+ super ^ @field.hash
+ end
+
+ def eql?(other)
+ super &&
+ self.field == other.field
+ end
+ alias :== :eql?
+ end
+ end
+end
diff --git a/activerecord/lib/arel/nodes/false.rb b/activerecord/lib/arel/nodes/false.rb
new file mode 100644
index 0000000000..1e5bf04be5
--- /dev/null
+++ b/activerecord/lib/arel/nodes/false.rb
@@ -0,0 +1,16 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module Nodes
+ class False < Arel::Nodes::NodeExpression
+ def hash
+ self.class.hash
+ end
+
+ def eql?(other)
+ self.class == other.class
+ end
+ alias :== :eql?
+ end
+ end
+end
diff --git a/activerecord/lib/arel/nodes/full_outer_join.rb b/activerecord/lib/arel/nodes/full_outer_join.rb
new file mode 100644
index 0000000000..91bb81f2e3
--- /dev/null
+++ b/activerecord/lib/arel/nodes/full_outer_join.rb
@@ -0,0 +1,8 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module Nodes
+ class FullOuterJoin < Arel::Nodes::Join
+ end
+ end
+end
diff --git a/activerecord/lib/arel/nodes/function.rb b/activerecord/lib/arel/nodes/function.rb
new file mode 100644
index 0000000000..0a439b39f5
--- /dev/null
+++ b/activerecord/lib/arel/nodes/function.rb
@@ -0,0 +1,44 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module Nodes
+ class Function < Arel::Nodes::NodeExpression
+ include Arel::WindowPredications
+ attr_accessor :expressions, :alias, :distinct
+
+ def initialize(expr, aliaz = nil)
+ super()
+ @expressions = expr
+ @alias = aliaz && SqlLiteral.new(aliaz)
+ @distinct = false
+ end
+
+ def as(aliaz)
+ self.alias = SqlLiteral.new(aliaz)
+ self
+ end
+
+ def hash
+ [@expressions, @alias, @distinct].hash
+ end
+
+ def eql?(other)
+ self.class == other.class &&
+ self.expressions == other.expressions &&
+ self.alias == other.alias &&
+ self.distinct == other.distinct
+ end
+ alias :== :eql?
+ end
+
+ %w{
+ Sum
+ Exists
+ Max
+ Min
+ Avg
+ }.each do |name|
+ const_set(name, Class.new(Function))
+ end
+ end
+end
diff --git a/activerecord/lib/arel/nodes/grouping.rb b/activerecord/lib/arel/nodes/grouping.rb
new file mode 100644
index 0000000000..4d0bd69d4d
--- /dev/null
+++ b/activerecord/lib/arel/nodes/grouping.rb
@@ -0,0 +1,8 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module Nodes
+ class Grouping < Unary
+ end
+ end
+end
diff --git a/activerecord/lib/arel/nodes/in.rb b/activerecord/lib/arel/nodes/in.rb
new file mode 100644
index 0000000000..2be45d6f99
--- /dev/null
+++ b/activerecord/lib/arel/nodes/in.rb
@@ -0,0 +1,8 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module Nodes
+ class In < Equality
+ end
+ end
+end
diff --git a/activerecord/lib/arel/nodes/infix_operation.rb b/activerecord/lib/arel/nodes/infix_operation.rb
new file mode 100644
index 0000000000..bc7e20dcc6
--- /dev/null
+++ b/activerecord/lib/arel/nodes/infix_operation.rb
@@ -0,0 +1,80 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module Nodes
+ class InfixOperation < Binary
+ include Arel::Expressions
+ include Arel::Predications
+ include Arel::OrderPredications
+ include Arel::AliasPredication
+ include Arel::Math
+
+ attr_reader :operator
+
+ def initialize(operator, left, right)
+ super(left, right)
+ @operator = operator
+ end
+ end
+
+ class Multiplication < InfixOperation
+ def initialize(left, right)
+ super(:*, left, right)
+ end
+ end
+
+ class Division < InfixOperation
+ def initialize(left, right)
+ super(:/, left, right)
+ end
+ end
+
+ class Addition < InfixOperation
+ def initialize(left, right)
+ super(:+, left, right)
+ end
+ end
+
+ class Subtraction < InfixOperation
+ def initialize(left, right)
+ super(:-, left, right)
+ end
+ end
+
+ class Concat < InfixOperation
+ def initialize(left, right)
+ super("||", left, right)
+ end
+ end
+
+ class BitwiseAnd < InfixOperation
+ def initialize(left, right)
+ super(:&, left, right)
+ end
+ end
+
+ class BitwiseOr < InfixOperation
+ def initialize(left, right)
+ super(:|, left, right)
+ end
+ end
+
+ class BitwiseXor < InfixOperation
+ def initialize(left, right)
+ super(:^, left, right)
+ end
+ end
+
+ class BitwiseShiftLeft < InfixOperation
+ def initialize(left, right)
+ super(:<<, left, right)
+ end
+ end
+
+ class BitwiseShiftRight < InfixOperation
+ def initialize(left, right)
+ super(:>>, left, right)
+ end
+ end
+ end
+end
diff --git a/activerecord/lib/arel/nodes/inner_join.rb b/activerecord/lib/arel/nodes/inner_join.rb
new file mode 100644
index 0000000000..519fafad09
--- /dev/null
+++ b/activerecord/lib/arel/nodes/inner_join.rb
@@ -0,0 +1,8 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module Nodes
+ class InnerJoin < Arel::Nodes::Join
+ end
+ end
+end
diff --git a/activerecord/lib/arel/nodes/insert_statement.rb b/activerecord/lib/arel/nodes/insert_statement.rb
new file mode 100644
index 0000000000..d28fd1f6c8
--- /dev/null
+++ b/activerecord/lib/arel/nodes/insert_statement.rb
@@ -0,0 +1,37 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module Nodes
+ class InsertStatement < Arel::Nodes::Node
+ attr_accessor :relation, :columns, :values, :select
+
+ def initialize
+ super()
+ @relation = nil
+ @columns = []
+ @values = nil
+ @select = nil
+ end
+
+ def initialize_copy(other)
+ super
+ @columns = @columns.clone
+ @values = @values.clone if @values
+ @select = @select.clone if @select
+ end
+
+ def hash
+ [@relation, @columns, @values, @select].hash
+ end
+
+ def eql?(other)
+ self.class == other.class &&
+ self.relation == other.relation &&
+ self.columns == other.columns &&
+ self.select == other.select &&
+ self.values == other.values
+ end
+ alias :== :eql?
+ end
+ end
+end
diff --git a/activerecord/lib/arel/nodes/join_source.rb b/activerecord/lib/arel/nodes/join_source.rb
new file mode 100644
index 0000000000..abf0944623
--- /dev/null
+++ b/activerecord/lib/arel/nodes/join_source.rb
@@ -0,0 +1,20 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module Nodes
+ ###
+ # Class that represents a join source
+ #
+ # http://www.sqlite.org/syntaxdiagrams.html#join-source
+
+ class JoinSource < Arel::Nodes::Binary
+ def initialize(single_source, joinop = [])
+ super
+ end
+
+ def empty?
+ !left && right.empty?
+ end
+ end
+ end
+end
diff --git a/activerecord/lib/arel/nodes/matches.rb b/activerecord/lib/arel/nodes/matches.rb
new file mode 100644
index 0000000000..fd5734f4bd
--- /dev/null
+++ b/activerecord/lib/arel/nodes/matches.rb
@@ -0,0 +1,18 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module Nodes
+ class Matches < Binary
+ attr_reader :escape
+ attr_accessor :case_sensitive
+
+ def initialize(left, right, escape = nil, case_sensitive = false)
+ super(left, right)
+ @escape = escape && Nodes.build_quoted(escape)
+ @case_sensitive = case_sensitive
+ end
+ end
+
+ class DoesNotMatch < Matches; end
+ end
+end
diff --git a/activerecord/lib/arel/nodes/named_function.rb b/activerecord/lib/arel/nodes/named_function.rb
new file mode 100644
index 0000000000..126462d6d6
--- /dev/null
+++ b/activerecord/lib/arel/nodes/named_function.rb
@@ -0,0 +1,23 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module Nodes
+ class NamedFunction < Arel::Nodes::Function
+ attr_accessor :name
+
+ def initialize(name, expr, aliaz = nil)
+ super(expr, aliaz)
+ @name = name
+ end
+
+ def hash
+ super ^ @name.hash
+ end
+
+ def eql?(other)
+ super && self.name == other.name
+ end
+ alias :== :eql?
+ end
+ end
+end
diff --git a/activerecord/lib/arel/nodes/node.rb b/activerecord/lib/arel/nodes/node.rb
new file mode 100644
index 0000000000..8086102bde
--- /dev/null
+++ b/activerecord/lib/arel/nodes/node.rb
@@ -0,0 +1,50 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module Nodes
+ ###
+ # Abstract base class for all AST nodes
+ class Node
+ include Arel::FactoryMethods
+ include Enumerable
+
+ ###
+ # Factory method to create a Nodes::Not node that has the recipient of
+ # the caller as a child.
+ def not
+ Nodes::Not.new self
+ end
+
+ ###
+ # Factory method to create a Nodes::Grouping node that has an Nodes::Or
+ # node as a child.
+ def or(right)
+ Nodes::Grouping.new Nodes::Or.new(self, right)
+ end
+
+ ###
+ # Factory method to create an Nodes::And node.
+ def and(right)
+ Nodes::And.new [self, right]
+ end
+
+ # FIXME: this method should go away. I don't like people calling
+ # to_sql on non-head nodes. This forces us to walk the AST until we
+ # can find a node that has a "relation" member.
+ #
+ # Maybe we should just use `Table.engine`? :'(
+ def to_sql(engine = Table.engine)
+ collector = Arel::Collectors::SQLString.new
+ collector = engine.connection.visitor.accept self, collector
+ collector.value
+ end
+
+ # Iterate through AST, nodes will be yielded depth-first
+ def each(&block)
+ return enum_for(:each) unless block_given?
+
+ ::Arel::Visitors::DepthFirst.new(block).accept self
+ end
+ end
+ end
+end
diff --git a/activerecord/lib/arel/nodes/node_expression.rb b/activerecord/lib/arel/nodes/node_expression.rb
new file mode 100644
index 0000000000..cbcfaba37c
--- /dev/null
+++ b/activerecord/lib/arel/nodes/node_expression.rb
@@ -0,0 +1,13 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module Nodes
+ class NodeExpression < Arel::Nodes::Node
+ include Arel::Expressions
+ include Arel::Predications
+ include Arel::AliasPredication
+ include Arel::OrderPredications
+ include Arel::Math
+ end
+ end
+end
diff --git a/activerecord/lib/arel/nodes/outer_join.rb b/activerecord/lib/arel/nodes/outer_join.rb
new file mode 100644
index 0000000000..0a3042be61
--- /dev/null
+++ b/activerecord/lib/arel/nodes/outer_join.rb
@@ -0,0 +1,8 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module Nodes
+ class OuterJoin < Arel::Nodes::Join
+ end
+ end
+end
diff --git a/activerecord/lib/arel/nodes/over.rb b/activerecord/lib/arel/nodes/over.rb
new file mode 100644
index 0000000000..91176764a9
--- /dev/null
+++ b/activerecord/lib/arel/nodes/over.rb
@@ -0,0 +1,15 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module Nodes
+ class Over < Binary
+ include Arel::AliasPredication
+
+ def initialize(left, right = nil)
+ super(left, right)
+ end
+
+ def operator; "OVER" end
+ end
+ end
+end
diff --git a/activerecord/lib/arel/nodes/regexp.rb b/activerecord/lib/arel/nodes/regexp.rb
new file mode 100644
index 0000000000..7c25095569
--- /dev/null
+++ b/activerecord/lib/arel/nodes/regexp.rb
@@ -0,0 +1,16 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module Nodes
+ class Regexp < Binary
+ attr_accessor :case_sensitive
+
+ def initialize(left, right, case_sensitive = true)
+ super(left, right)
+ @case_sensitive = case_sensitive
+ end
+ end
+
+ class NotRegexp < Regexp; end
+ end
+end
diff --git a/activerecord/lib/arel/nodes/right_outer_join.rb b/activerecord/lib/arel/nodes/right_outer_join.rb
new file mode 100644
index 0000000000..04ed4aaa78
--- /dev/null
+++ b/activerecord/lib/arel/nodes/right_outer_join.rb
@@ -0,0 +1,8 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module Nodes
+ class RightOuterJoin < Arel::Nodes::Join
+ end
+ end
+end
diff --git a/activerecord/lib/arel/nodes/select_core.rb b/activerecord/lib/arel/nodes/select_core.rb
new file mode 100644
index 0000000000..73461ff683
--- /dev/null
+++ b/activerecord/lib/arel/nodes/select_core.rb
@@ -0,0 +1,63 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module Nodes
+ class SelectCore < Arel::Nodes::Node
+ attr_accessor :projections, :wheres, :groups, :windows
+ attr_accessor :havings, :source, :set_quantifier
+
+ def initialize
+ super()
+ @source = JoinSource.new nil
+
+ # https://ronsavage.github.io/SQL/sql-92.bnf.html#set%20quantifier
+ @set_quantifier = nil
+ @projections = []
+ @wheres = []
+ @groups = []
+ @havings = []
+ @windows = []
+ end
+
+ def from
+ @source.left
+ end
+
+ def from=(value)
+ @source.left = value
+ end
+
+ alias :froms= :from=
+ alias :froms :from
+
+ def initialize_copy(other)
+ super
+ @source = @source.clone if @source
+ @projections = @projections.clone
+ @wheres = @wheres.clone
+ @groups = @groups.clone
+ @havings = @havings.clone
+ @windows = @windows.clone
+ end
+
+ def hash
+ [
+ @source, @set_quantifier, @projections,
+ @wheres, @groups, @havings, @windows
+ ].hash
+ end
+
+ def eql?(other)
+ self.class == other.class &&
+ self.source == other.source &&
+ self.set_quantifier == other.set_quantifier &&
+ self.projections == other.projections &&
+ self.wheres == other.wheres &&
+ self.groups == other.groups &&
+ self.havings == other.havings &&
+ self.windows == other.windows
+ end
+ alias :== :eql?
+ end
+ end
+end
diff --git a/activerecord/lib/arel/nodes/select_statement.rb b/activerecord/lib/arel/nodes/select_statement.rb
new file mode 100644
index 0000000000..eff5dad939
--- /dev/null
+++ b/activerecord/lib/arel/nodes/select_statement.rb
@@ -0,0 +1,41 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module Nodes
+ class SelectStatement < Arel::Nodes::NodeExpression
+ attr_reader :cores
+ attr_accessor :limit, :orders, :lock, :offset, :with
+
+ def initialize(cores = [SelectCore.new])
+ super()
+ @cores = cores
+ @orders = []
+ @limit = nil
+ @lock = nil
+ @offset = nil
+ @with = nil
+ end
+
+ def initialize_copy(other)
+ super
+ @cores = @cores.map { |x| x.clone }
+ @orders = @orders.map { |x| x.clone }
+ end
+
+ def hash
+ [@cores, @orders, @limit, @lock, @offset, @with].hash
+ end
+
+ def eql?(other)
+ self.class == other.class &&
+ self.cores == other.cores &&
+ self.orders == other.orders &&
+ self.limit == other.limit &&
+ self.lock == other.lock &&
+ self.offset == other.offset &&
+ self.with == other.with
+ end
+ alias :== :eql?
+ end
+ end
+end
diff --git a/activerecord/lib/arel/nodes/sql_literal.rb b/activerecord/lib/arel/nodes/sql_literal.rb
new file mode 100644
index 0000000000..d25a8521b7
--- /dev/null
+++ b/activerecord/lib/arel/nodes/sql_literal.rb
@@ -0,0 +1,16 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module Nodes
+ class SqlLiteral < String
+ include Arel::Expressions
+ include Arel::Predications
+ include Arel::AliasPredication
+ include Arel::OrderPredications
+
+ def encode_with(coder)
+ coder.scalar = self.to_s
+ end
+ end
+ end
+end
diff --git a/activerecord/lib/arel/nodes/string_join.rb b/activerecord/lib/arel/nodes/string_join.rb
new file mode 100644
index 0000000000..86027fcab7
--- /dev/null
+++ b/activerecord/lib/arel/nodes/string_join.rb
@@ -0,0 +1,11 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module Nodes
+ class StringJoin < Arel::Nodes::Join
+ def initialize(left, right = nil)
+ super
+ end
+ end
+ end
+end
diff --git a/activerecord/lib/arel/nodes/table_alias.rb b/activerecord/lib/arel/nodes/table_alias.rb
new file mode 100644
index 0000000000..f95ca16a3d
--- /dev/null
+++ b/activerecord/lib/arel/nodes/table_alias.rb
@@ -0,0 +1,27 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module Nodes
+ class TableAlias < Arel::Nodes::Binary
+ alias :name :right
+ alias :relation :left
+ alias :table_alias :name
+
+ def [](name)
+ Attribute.new(self, name)
+ end
+
+ def table_name
+ relation.respond_to?(:name) ? relation.name : name
+ end
+
+ def type_cast_for_database(*args)
+ relation.type_cast_for_database(*args)
+ end
+
+ def able_to_type_cast?
+ relation.respond_to?(:able_to_type_cast?) && relation.able_to_type_cast?
+ end
+ end
+ end
+end
diff --git a/activerecord/lib/arel/nodes/terminal.rb b/activerecord/lib/arel/nodes/terminal.rb
new file mode 100644
index 0000000000..d84c453f1a
--- /dev/null
+++ b/activerecord/lib/arel/nodes/terminal.rb
@@ -0,0 +1,16 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module Nodes
+ class Distinct < Arel::Nodes::NodeExpression
+ def hash
+ self.class.hash
+ end
+
+ def eql?(other)
+ self.class == other.class
+ end
+ alias :== :eql?
+ end
+ end
+end
diff --git a/activerecord/lib/arel/nodes/true.rb b/activerecord/lib/arel/nodes/true.rb
new file mode 100644
index 0000000000..c891012969
--- /dev/null
+++ b/activerecord/lib/arel/nodes/true.rb
@@ -0,0 +1,16 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module Nodes
+ class True < Arel::Nodes::NodeExpression
+ def hash
+ self.class.hash
+ end
+
+ def eql?(other)
+ self.class == other.class
+ end
+ alias :== :eql?
+ end
+ end
+end
diff --git a/activerecord/lib/arel/nodes/unary.rb b/activerecord/lib/arel/nodes/unary.rb
new file mode 100644
index 0000000000..00639304e4
--- /dev/null
+++ b/activerecord/lib/arel/nodes/unary.rb
@@ -0,0 +1,44 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module Nodes
+ class Unary < Arel::Nodes::NodeExpression
+ attr_accessor :expr
+ alias :value :expr
+
+ def initialize(expr)
+ super()
+ @expr = expr
+ end
+
+ def hash
+ @expr.hash
+ end
+
+ def eql?(other)
+ self.class == other.class &&
+ self.expr == other.expr
+ end
+ alias :== :eql?
+ end
+
+ %w{
+ Bin
+ Cube
+ DistinctOn
+ Group
+ GroupingElement
+ GroupingSet
+ Lateral
+ Limit
+ Lock
+ Not
+ Offset
+ On
+ Ordering
+ RollUp
+ }.each do |name|
+ const_set(name, Class.new(Unary))
+ end
+ end
+end
diff --git a/activerecord/lib/arel/nodes/unary_operation.rb b/activerecord/lib/arel/nodes/unary_operation.rb
new file mode 100644
index 0000000000..524282ac84
--- /dev/null
+++ b/activerecord/lib/arel/nodes/unary_operation.rb
@@ -0,0 +1,20 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module Nodes
+ class UnaryOperation < Unary
+ attr_reader :operator
+
+ def initialize(operator, operand)
+ super(operand)
+ @operator = operator
+ end
+ end
+
+ class BitwiseNot < UnaryOperation
+ def initialize(operand)
+ super(:~, operand)
+ end
+ end
+ end
+end
diff --git a/activerecord/lib/arel/nodes/unqualified_column.rb b/activerecord/lib/arel/nodes/unqualified_column.rb
new file mode 100644
index 0000000000..7c3e0720d7
--- /dev/null
+++ b/activerecord/lib/arel/nodes/unqualified_column.rb
@@ -0,0 +1,22 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module Nodes
+ class UnqualifiedColumn < Arel::Nodes::Unary
+ alias :attribute :expr
+ alias :attribute= :expr=
+
+ def relation
+ @expr.relation
+ end
+
+ def column
+ @expr.column
+ end
+
+ def name
+ @expr.name
+ end
+ end
+ end
+end
diff --git a/activerecord/lib/arel/nodes/update_statement.rb b/activerecord/lib/arel/nodes/update_statement.rb
new file mode 100644
index 0000000000..cfaa19e392
--- /dev/null
+++ b/activerecord/lib/arel/nodes/update_statement.rb
@@ -0,0 +1,41 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module Nodes
+ class UpdateStatement < Arel::Nodes::Node
+ attr_accessor :relation, :wheres, :values, :orders, :limit, :offset, :key
+
+ def initialize
+ @relation = nil
+ @wheres = []
+ @values = []
+ @orders = []
+ @limit = nil
+ @offset = nil
+ @key = nil
+ end
+
+ def initialize_copy(other)
+ super
+ @wheres = @wheres.clone
+ @values = @values.clone
+ end
+
+ def hash
+ [@relation, @wheres, @values, @orders, @limit, @offset, @key].hash
+ end
+
+ def eql?(other)
+ self.class == other.class &&
+ self.relation == other.relation &&
+ self.wheres == other.wheres &&
+ self.values == other.values &&
+ self.orders == other.orders &&
+ self.limit == other.limit &&
+ self.offset == other.offset &&
+ self.key == other.key
+ end
+ alias :== :eql?
+ end
+ end
+end
diff --git a/activerecord/lib/arel/nodes/values.rb b/activerecord/lib/arel/nodes/values.rb
new file mode 100644
index 0000000000..650248dc04
--- /dev/null
+++ b/activerecord/lib/arel/nodes/values.rb
@@ -0,0 +1,16 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module Nodes
+ class Values < Arel::Nodes::Binary
+ alias :expressions :left
+ alias :expressions= :left=
+ alias :columns :right
+ alias :columns= :right=
+
+ def initialize(exprs, columns = [])
+ super
+ end
+ end
+ end
+end
diff --git a/activerecord/lib/arel/nodes/values_list.rb b/activerecord/lib/arel/nodes/values_list.rb
new file mode 100644
index 0000000000..27109848e4
--- /dev/null
+++ b/activerecord/lib/arel/nodes/values_list.rb
@@ -0,0 +1,24 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module Nodes
+ class ValuesList < Node
+ attr_reader :rows
+
+ def initialize(rows)
+ @rows = rows
+ super()
+ end
+
+ def hash
+ @rows.hash
+ end
+
+ def eql?(other)
+ self.class == other.class &&
+ self.rows == other.rows
+ end
+ alias :== :eql?
+ end
+ end
+end
diff --git a/activerecord/lib/arel/nodes/window.rb b/activerecord/lib/arel/nodes/window.rb
new file mode 100644
index 0000000000..4916fc7fbe
--- /dev/null
+++ b/activerecord/lib/arel/nodes/window.rb
@@ -0,0 +1,126 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module Nodes
+ class Window < Arel::Nodes::Node
+ attr_accessor :orders, :framing, :partitions
+
+ def initialize
+ @orders = []
+ @partitions = []
+ @framing = nil
+ end
+
+ def order(*expr)
+ # FIXME: We SHOULD NOT be converting these to SqlLiteral automatically
+ @orders.concat expr.map { |x|
+ String === x || Symbol === x ? Nodes::SqlLiteral.new(x.to_s) : x
+ }
+ self
+ end
+
+ def partition(*expr)
+ # FIXME: We SHOULD NOT be converting these to SqlLiteral automatically
+ @partitions.concat expr.map { |x|
+ String === x || Symbol === x ? Nodes::SqlLiteral.new(x.to_s) : x
+ }
+ self
+ end
+
+ def frame(expr)
+ @framing = expr
+ end
+
+ def rows(expr = nil)
+ if @framing
+ Rows.new(expr)
+ else
+ frame(Rows.new(expr))
+ end
+ end
+
+ def range(expr = nil)
+ if @framing
+ Range.new(expr)
+ else
+ frame(Range.new(expr))
+ end
+ end
+
+ def initialize_copy(other)
+ super
+ @orders = @orders.map { |x| x.clone }
+ end
+
+ def hash
+ [@orders, @framing].hash
+ end
+
+ def eql?(other)
+ self.class == other.class &&
+ self.orders == other.orders &&
+ self.framing == other.framing &&
+ self.partitions == other.partitions
+ end
+ alias :== :eql?
+ end
+
+ class NamedWindow < Window
+ attr_accessor :name
+
+ def initialize(name)
+ super()
+ @name = name
+ end
+
+ def initialize_copy(other)
+ super
+ @name = other.name.clone
+ end
+
+ def hash
+ super ^ @name.hash
+ end
+
+ def eql?(other)
+ super && self.name == other.name
+ end
+ alias :== :eql?
+ end
+
+ class Rows < Unary
+ def initialize(expr = nil)
+ super(expr)
+ end
+ end
+
+ class Range < Unary
+ def initialize(expr = nil)
+ super(expr)
+ end
+ end
+
+ class CurrentRow < Node
+ def hash
+ self.class.hash
+ end
+
+ def eql?(other)
+ self.class == other.class
+ end
+ alias :== :eql?
+ end
+
+ class Preceding < Unary
+ def initialize(expr = nil)
+ super(expr)
+ end
+ end
+
+ class Following < Unary
+ def initialize(expr = nil)
+ super(expr)
+ end
+ end
+ end
+end
diff --git a/activerecord/lib/arel/nodes/with.rb b/activerecord/lib/arel/nodes/with.rb
new file mode 100644
index 0000000000..157bdcaa08
--- /dev/null
+++ b/activerecord/lib/arel/nodes/with.rb
@@ -0,0 +1,11 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module Nodes
+ class With < Arel::Nodes::Unary
+ alias children expr
+ end
+
+ class WithRecursive < With; end
+ end
+end
diff --git a/activerecord/lib/arel/order_predications.rb b/activerecord/lib/arel/order_predications.rb
new file mode 100644
index 0000000000..d785bbba92
--- /dev/null
+++ b/activerecord/lib/arel/order_predications.rb
@@ -0,0 +1,13 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module OrderPredications
+ def asc
+ Nodes::Ascending.new self
+ end
+
+ def desc
+ Nodes::Descending.new self
+ end
+ end
+end
diff --git a/activerecord/lib/arel/predications.rb b/activerecord/lib/arel/predications.rb
new file mode 100644
index 0000000000..77502dd199
--- /dev/null
+++ b/activerecord/lib/arel/predications.rb
@@ -0,0 +1,249 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module Predications
+ def not_eq(other)
+ Nodes::NotEqual.new self, quoted_node(other)
+ end
+
+ def not_eq_any(others)
+ grouping_any :not_eq, others
+ end
+
+ def not_eq_all(others)
+ grouping_all :not_eq, others
+ end
+
+ def eq(other)
+ Nodes::Equality.new self, quoted_node(other)
+ end
+
+ def is_not_distinct_from(other)
+ Nodes::IsNotDistinctFrom.new self, quoted_node(other)
+ end
+
+ def is_distinct_from(other)
+ Nodes::IsDistinctFrom.new self, quoted_node(other)
+ end
+
+ def eq_any(others)
+ grouping_any :eq, others
+ end
+
+ def eq_all(others)
+ grouping_all :eq, quoted_array(others)
+ end
+
+ def between(other)
+ if equals_quoted?(other.begin, -Float::INFINITY)
+ if equals_quoted?(other.end, Float::INFINITY)
+ not_in([])
+ elsif other.exclude_end?
+ lt(other.end)
+ else
+ lteq(other.end)
+ end
+ elsif equals_quoted?(other.end, Float::INFINITY)
+ gteq(other.begin)
+ elsif other.exclude_end?
+ gteq(other.begin).and(lt(other.end))
+ else
+ left = quoted_node(other.begin)
+ right = quoted_node(other.end)
+ Nodes::Between.new(self, left.and(right))
+ end
+ end
+
+ def in(other)
+ case other
+ when Arel::SelectManager
+ Arel::Nodes::In.new(self, other.ast)
+ when Range
+ if $VERBOSE
+ warn <<-eowarn
+Passing a range to `#in` is deprecated. Call `#between`, instead.
+ eowarn
+ end
+ between(other)
+ when Enumerable
+ Nodes::In.new self, quoted_array(other)
+ else
+ Nodes::In.new self, quoted_node(other)
+ end
+ end
+
+ def in_any(others)
+ grouping_any :in, others
+ end
+
+ def in_all(others)
+ grouping_all :in, others
+ end
+
+ def not_between(other)
+ if equals_quoted?(other.begin, -Float::INFINITY)
+ if equals_quoted?(other.end, Float::INFINITY)
+ self.in([])
+ elsif other.exclude_end?
+ gteq(other.end)
+ else
+ gt(other.end)
+ end
+ elsif equals_quoted?(other.end, Float::INFINITY)
+ lt(other.begin)
+ else
+ left = lt(other.begin)
+ right = if other.exclude_end?
+ gteq(other.end)
+ else
+ gt(other.end)
+ end
+ left.or(right)
+ end
+ end
+
+ def not_in(other)
+ case other
+ when Arel::SelectManager
+ Arel::Nodes::NotIn.new(self, other.ast)
+ when Range
+ if $VERBOSE
+ warn <<-eowarn
+Passing a range to `#not_in` is deprecated. Call `#not_between`, instead.
+ eowarn
+ end
+ not_between(other)
+ when Enumerable
+ Nodes::NotIn.new self, quoted_array(other)
+ else
+ Nodes::NotIn.new self, quoted_node(other)
+ end
+ end
+
+ def not_in_any(others)
+ grouping_any :not_in, others
+ end
+
+ def not_in_all(others)
+ grouping_all :not_in, others
+ end
+
+ def matches(other, escape = nil, case_sensitive = false)
+ Nodes::Matches.new self, quoted_node(other), escape, case_sensitive
+ end
+
+ def matches_regexp(other, case_sensitive = true)
+ Nodes::Regexp.new self, quoted_node(other), case_sensitive
+ end
+
+ def matches_any(others, escape = nil, case_sensitive = false)
+ grouping_any :matches, others, escape, case_sensitive
+ end
+
+ def matches_all(others, escape = nil, case_sensitive = false)
+ grouping_all :matches, others, escape, case_sensitive
+ end
+
+ def does_not_match(other, escape = nil, case_sensitive = false)
+ Nodes::DoesNotMatch.new self, quoted_node(other), escape, case_sensitive
+ end
+
+ def does_not_match_regexp(other, case_sensitive = true)
+ Nodes::NotRegexp.new self, quoted_node(other), case_sensitive
+ end
+
+ def does_not_match_any(others, escape = nil)
+ grouping_any :does_not_match, others, escape
+ end
+
+ def does_not_match_all(others, escape = nil)
+ grouping_all :does_not_match, others, escape
+ end
+
+ def gteq(right)
+ Nodes::GreaterThanOrEqual.new self, quoted_node(right)
+ end
+
+ def gteq_any(others)
+ grouping_any :gteq, others
+ end
+
+ def gteq_all(others)
+ grouping_all :gteq, others
+ end
+
+ def gt(right)
+ Nodes::GreaterThan.new self, quoted_node(right)
+ end
+
+ def gt_any(others)
+ grouping_any :gt, others
+ end
+
+ def gt_all(others)
+ grouping_all :gt, others
+ end
+
+ def lt(right)
+ Nodes::LessThan.new self, quoted_node(right)
+ end
+
+ def lt_any(others)
+ grouping_any :lt, others
+ end
+
+ def lt_all(others)
+ grouping_all :lt, others
+ end
+
+ def lteq(right)
+ Nodes::LessThanOrEqual.new self, quoted_node(right)
+ end
+
+ def lteq_any(others)
+ grouping_any :lteq, others
+ end
+
+ def lteq_all(others)
+ grouping_all :lteq, others
+ end
+
+ def when(right)
+ Nodes::Case.new(self).when quoted_node(right)
+ end
+
+ def concat(other)
+ Nodes::Concat.new self, other
+ end
+
+ private
+
+ def grouping_any(method_id, others, *extras)
+ nodes = others.map { |expr| send(method_id, expr, *extras) }
+ Nodes::Grouping.new nodes.inject { |memo, node|
+ Nodes::Or.new(memo, node)
+ }
+ end
+
+ def grouping_all(method_id, others, *extras)
+ nodes = others.map { |expr| send(method_id, expr, *extras) }
+ Nodes::Grouping.new Nodes::And.new(nodes)
+ end
+
+ def quoted_node(other)
+ Nodes.build_quoted(other, self)
+ end
+
+ def quoted_array(others)
+ others.map { |v| quoted_node(v) }
+ end
+
+ def equals_quoted?(maybe_quoted, value)
+ if maybe_quoted.is_a?(Nodes::Quoted)
+ maybe_quoted.val == value
+ else
+ maybe_quoted == value
+ end
+ end
+ end
+end
diff --git a/activerecord/lib/arel/select_manager.rb b/activerecord/lib/arel/select_manager.rb
new file mode 100644
index 0000000000..a2b2838a3d
--- /dev/null
+++ b/activerecord/lib/arel/select_manager.rb
@@ -0,0 +1,271 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ class SelectManager < Arel::TreeManager
+ include Arel::Crud
+
+ STRING_OR_SYMBOL_CLASS = [Symbol, String]
+
+ def initialize(table = nil)
+ super()
+ @ast = Nodes::SelectStatement.new
+ @ctx = @ast.cores.last
+ from table
+ end
+
+ def initialize_copy(other)
+ super
+ @ctx = @ast.cores.last
+ end
+
+ def limit
+ @ast.limit && @ast.limit.expr
+ end
+ alias :taken :limit
+
+ def constraints
+ @ctx.wheres
+ end
+
+ def offset
+ @ast.offset && @ast.offset.expr
+ end
+
+ def skip(amount)
+ if amount
+ @ast.offset = Nodes::Offset.new(amount)
+ else
+ @ast.offset = nil
+ end
+ self
+ end
+ alias :offset= :skip
+
+ ###
+ # Produces an Arel::Nodes::Exists node
+ def exists
+ Arel::Nodes::Exists.new @ast
+ end
+
+ def as(other)
+ create_table_alias grouping(@ast), Nodes::SqlLiteral.new(other)
+ end
+
+ def lock(locking = Arel.sql("FOR UPDATE"))
+ case locking
+ when true
+ locking = Arel.sql("FOR UPDATE")
+ when Arel::Nodes::SqlLiteral
+ when String
+ locking = Arel.sql locking
+ end
+
+ @ast.lock = Nodes::Lock.new(locking)
+ self
+ end
+
+ def locked
+ @ast.lock
+ end
+
+ def on(*exprs)
+ @ctx.source.right.last.right = Nodes::On.new(collapse(exprs))
+ self
+ end
+
+ def group(*columns)
+ columns.each do |column|
+ # FIXME: backwards compat
+ column = Nodes::SqlLiteral.new(column) if String === column
+ column = Nodes::SqlLiteral.new(column.to_s) if Symbol === column
+
+ @ctx.groups.push Nodes::Group.new column
+ end
+ self
+ end
+
+ def from(table)
+ table = Nodes::SqlLiteral.new(table) if String === table
+
+ case table
+ when Nodes::Join
+ @ctx.source.right << table
+ else
+ @ctx.source.left = table
+ end
+
+ self
+ end
+
+ def froms
+ @ast.cores.map { |x| x.from }.compact
+ end
+
+ def join(relation, klass = Nodes::InnerJoin)
+ return self unless relation
+
+ case relation
+ when String, Nodes::SqlLiteral
+ raise EmptyJoinError if relation.empty?
+ klass = Nodes::StringJoin
+ end
+
+ @ctx.source.right << create_join(relation, nil, klass)
+ self
+ end
+
+ def outer_join(relation)
+ join(relation, Nodes::OuterJoin)
+ end
+
+ def having(expr)
+ @ctx.havings << expr
+ self
+ end
+
+ def window(name)
+ window = Nodes::NamedWindow.new(name)
+ @ctx.windows.push window
+ window
+ end
+
+ def project(*projections)
+ # FIXME: converting these to SQLLiterals is probably not good, but
+ # rails tests require it.
+ @ctx.projections.concat projections.map { |x|
+ STRING_OR_SYMBOL_CLASS.include?(x.class) ? Nodes::SqlLiteral.new(x.to_s) : x
+ }
+ self
+ end
+
+ def projections
+ @ctx.projections
+ end
+
+ def projections=(projections)
+ @ctx.projections = projections
+ end
+
+ def distinct(value = true)
+ if value
+ @ctx.set_quantifier = Arel::Nodes::Distinct.new
+ else
+ @ctx.set_quantifier = nil
+ end
+ self
+ end
+
+ def distinct_on(value)
+ if value
+ @ctx.set_quantifier = Arel::Nodes::DistinctOn.new(value)
+ else
+ @ctx.set_quantifier = nil
+ end
+ self
+ end
+
+ def order(*expr)
+ # FIXME: We SHOULD NOT be converting these to SqlLiteral automatically
+ @ast.orders.concat expr.map { |x|
+ STRING_OR_SYMBOL_CLASS.include?(x.class) ? Nodes::SqlLiteral.new(x.to_s) : x
+ }
+ self
+ end
+
+ def orders
+ @ast.orders
+ end
+
+ def where_sql(engine = Table.engine)
+ return if @ctx.wheres.empty?
+
+ viz = Visitors::WhereSql.new(engine.connection.visitor, engine.connection)
+ Nodes::SqlLiteral.new viz.accept(@ctx, Collectors::SQLString.new).value
+ end
+
+ def union(operation, other = nil)
+ if other
+ node_class = Nodes.const_get("Union#{operation.to_s.capitalize}")
+ else
+ other = operation
+ node_class = Nodes::Union
+ end
+
+ node_class.new self.ast, other.ast
+ end
+
+ def intersect(other)
+ Nodes::Intersect.new ast, other.ast
+ end
+
+ def except(other)
+ Nodes::Except.new ast, other.ast
+ end
+ alias :minus :except
+
+ def lateral(table_name = nil)
+ base = table_name.nil? ? ast : as(table_name)
+ Nodes::Lateral.new(base)
+ end
+
+ def with(*subqueries)
+ if subqueries.first.is_a? Symbol
+ node_class = Nodes.const_get("With#{subqueries.shift.to_s.capitalize}")
+ else
+ node_class = Nodes::With
+ end
+ @ast.with = node_class.new(subqueries.flatten)
+
+ self
+ end
+
+ def take(limit)
+ if limit
+ @ast.limit = Nodes::Limit.new(limit)
+ else
+ @ast.limit = nil
+ end
+ self
+ end
+ alias limit= take
+
+ def join_sources
+ @ctx.source.right
+ end
+
+ def source
+ @ctx.source
+ end
+
+ class Row < Struct.new(:data) # :nodoc:
+ def id
+ data["id"]
+ end
+
+ def method_missing(name, *args)
+ name = name.to_s
+ return data[name] if data.key?(name)
+ super
+ end
+ end
+
+ private
+ def collapse(exprs)
+ exprs = exprs.compact
+ exprs.map! { |expr|
+ if String === expr
+ # FIXME: Don't do this automatically
+ Arel.sql(expr)
+ else
+ expr
+ end
+ }
+
+ if exprs.length == 1
+ exprs.first
+ else
+ create_and exprs
+ end
+ end
+ end
+end
diff --git a/activerecord/lib/arel/table.rb b/activerecord/lib/arel/table.rb
new file mode 100644
index 0000000000..c40c68715a
--- /dev/null
+++ b/activerecord/lib/arel/table.rb
@@ -0,0 +1,110 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ class Table
+ include Arel::Crud
+ include Arel::FactoryMethods
+
+ @engine = nil
+ class << self; attr_accessor :engine; end
+
+ attr_accessor :name, :table_alias
+
+ # TableAlias and Table both have a #table_name which is the name of the underlying table
+ alias :table_name :name
+
+ def initialize(name, as: nil, type_caster: nil)
+ @name = name.to_s
+ @type_caster = type_caster
+
+ # Sometime AR sends an :as parameter to table, to let the table know
+ # that it is an Alias. We may want to override new, and return a
+ # TableAlias node?
+ if as.to_s == @name
+ as = nil
+ end
+ @table_alias = as
+ end
+
+ def alias(name = "#{self.name}_2")
+ Nodes::TableAlias.new(self, name)
+ end
+
+ def from
+ SelectManager.new(self)
+ end
+
+ def join(relation, klass = Nodes::InnerJoin)
+ return from unless relation
+
+ case relation
+ when String, Nodes::SqlLiteral
+ raise EmptyJoinError if relation.empty?
+ klass = Nodes::StringJoin
+ end
+
+ from.join(relation, klass)
+ end
+
+ def outer_join(relation)
+ join(relation, Nodes::OuterJoin)
+ end
+
+ def group(*columns)
+ from.group(*columns)
+ end
+
+ def order(*expr)
+ from.order(*expr)
+ end
+
+ def where(condition)
+ from.where condition
+ end
+
+ def project(*things)
+ from.project(*things)
+ end
+
+ def take(amount)
+ from.take amount
+ end
+
+ def skip(amount)
+ from.skip amount
+ end
+
+ def having(expr)
+ from.having expr
+ end
+
+ def [](name)
+ ::Arel::Attribute.new self, name
+ end
+
+ def hash
+ # Perf note: aliases and table alias is excluded from the hash
+ # aliases can have a loop back to this table breaking hashes in parent
+ # relations, for the vast majority of cases @name is unique to a query
+ @name.hash
+ end
+
+ def eql?(other)
+ self.class == other.class &&
+ self.name == other.name &&
+ self.table_alias == other.table_alias
+ end
+ alias :== :eql?
+
+ def type_cast_for_database(attribute_name, value)
+ type_caster.type_cast_for_database(attribute_name, value)
+ end
+
+ def able_to_type_cast?
+ !type_caster.nil?
+ end
+
+ private
+ attr_reader :type_caster
+ end
+end
diff --git a/activerecord/lib/arel/tree_manager.rb b/activerecord/lib/arel/tree_manager.rb
new file mode 100644
index 0000000000..0476399618
--- /dev/null
+++ b/activerecord/lib/arel/tree_manager.rb
@@ -0,0 +1,72 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ class TreeManager
+ include Arel::FactoryMethods
+
+ module StatementMethods
+ def take(limit)
+ @ast.limit = Nodes::Limit.new(Nodes.build_quoted(limit)) if limit
+ self
+ end
+
+ def offset(offset)
+ @ast.offset = Nodes::Offset.new(Nodes.build_quoted(offset)) if offset
+ self
+ end
+
+ def order(*expr)
+ @ast.orders = expr
+ self
+ end
+
+ def key=(key)
+ @ast.key = Nodes.build_quoted(key)
+ end
+
+ def key
+ @ast.key
+ end
+
+ def wheres=(exprs)
+ @ast.wheres = exprs
+ end
+
+ def where(expr)
+ @ast.wheres << expr
+ self
+ end
+ end
+
+ attr_reader :ast
+
+ def initialize
+ @ctx = nil
+ end
+
+ def to_dot
+ collector = Arel::Collectors::PlainString.new
+ collector = Visitors::Dot.new.accept @ast, collector
+ collector.value
+ end
+
+ def to_sql(engine = Table.engine)
+ collector = Arel::Collectors::SQLString.new
+ collector = engine.connection.visitor.accept @ast, collector
+ collector.value
+ end
+
+ def initialize_copy(other)
+ super
+ @ast = @ast.clone
+ end
+
+ def where(expr)
+ if Arel::TreeManager === expr
+ expr = expr.ast
+ end
+ @ctx.wheres << expr
+ self
+ end
+ end
+end
diff --git a/activerecord/lib/arel/update_manager.rb b/activerecord/lib/arel/update_manager.rb
new file mode 100644
index 0000000000..a809dbb307
--- /dev/null
+++ b/activerecord/lib/arel/update_manager.rb
@@ -0,0 +1,34 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ class UpdateManager < Arel::TreeManager
+ include TreeManager::StatementMethods
+
+ def initialize
+ super
+ @ast = Nodes::UpdateStatement.new
+ @ctx = @ast
+ end
+
+ ###
+ # UPDATE +table+
+ def table(table)
+ @ast.relation = table
+ self
+ end
+
+ def set(values)
+ if String === values
+ @ast.values = [values]
+ else
+ @ast.values = values.map { |column, value|
+ Nodes::Assignment.new(
+ Nodes::UnqualifiedColumn.new(column),
+ value
+ )
+ }
+ end
+ self
+ end
+ end
+end
diff --git a/activerecord/lib/arel/visitors.rb b/activerecord/lib/arel/visitors.rb
new file mode 100644
index 0000000000..e350f52e65
--- /dev/null
+++ b/activerecord/lib/arel/visitors.rb
@@ -0,0 +1,20 @@
+# frozen_string_literal: true
+
+require "arel/visitors/visitor"
+require "arel/visitors/depth_first"
+require "arel/visitors/to_sql"
+require "arel/visitors/sqlite"
+require "arel/visitors/postgresql"
+require "arel/visitors/mysql"
+require "arel/visitors/mssql"
+require "arel/visitors/oracle"
+require "arel/visitors/oracle12"
+require "arel/visitors/where_sql"
+require "arel/visitors/dot"
+require "arel/visitors/ibm_db"
+require "arel/visitors/informix"
+
+module Arel # :nodoc: all
+ module Visitors
+ end
+end
diff --git a/activerecord/lib/arel/visitors/depth_first.rb b/activerecord/lib/arel/visitors/depth_first.rb
new file mode 100644
index 0000000000..92d309453c
--- /dev/null
+++ b/activerecord/lib/arel/visitors/depth_first.rb
@@ -0,0 +1,199 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module Visitors
+ class DepthFirst < Arel::Visitors::Visitor
+ def initialize(block = nil)
+ @block = block || Proc.new
+ super()
+ end
+
+ private
+
+ def visit(o)
+ super
+ @block.call o
+ end
+
+ def unary(o)
+ visit o.expr
+ end
+ alias :visit_Arel_Nodes_Else :unary
+ alias :visit_Arel_Nodes_Group :unary
+ alias :visit_Arel_Nodes_Cube :unary
+ alias :visit_Arel_Nodes_RollUp :unary
+ alias :visit_Arel_Nodes_GroupingSet :unary
+ alias :visit_Arel_Nodes_GroupingElement :unary
+ alias :visit_Arel_Nodes_Grouping :unary
+ alias :visit_Arel_Nodes_Having :unary
+ alias :visit_Arel_Nodes_Lateral :unary
+ alias :visit_Arel_Nodes_Limit :unary
+ alias :visit_Arel_Nodes_Not :unary
+ alias :visit_Arel_Nodes_Offset :unary
+ alias :visit_Arel_Nodes_On :unary
+ alias :visit_Arel_Nodes_Ordering :unary
+ alias :visit_Arel_Nodes_Ascending :unary
+ alias :visit_Arel_Nodes_Descending :unary
+ alias :visit_Arel_Nodes_UnqualifiedColumn :unary
+
+ def function(o)
+ visit o.expressions
+ visit o.alias
+ visit o.distinct
+ end
+ alias :visit_Arel_Nodes_Avg :function
+ alias :visit_Arel_Nodes_Exists :function
+ alias :visit_Arel_Nodes_Max :function
+ alias :visit_Arel_Nodes_Min :function
+ alias :visit_Arel_Nodes_Sum :function
+
+ def visit_Arel_Nodes_NamedFunction(o)
+ visit o.name
+ visit o.expressions
+ visit o.distinct
+ visit o.alias
+ end
+
+ def visit_Arel_Nodes_Count(o)
+ visit o.expressions
+ visit o.alias
+ visit o.distinct
+ end
+
+ def visit_Arel_Nodes_Case(o)
+ visit o.case
+ visit o.conditions
+ visit o.default
+ end
+
+ def nary(o)
+ o.children.each { |child| visit child }
+ end
+ alias :visit_Arel_Nodes_And :nary
+
+ def binary(o)
+ visit o.left
+ visit o.right
+ end
+ alias :visit_Arel_Nodes_As :binary
+ alias :visit_Arel_Nodes_Assignment :binary
+ alias :visit_Arel_Nodes_Between :binary
+ alias :visit_Arel_Nodes_Concat :binary
+ alias :visit_Arel_Nodes_DeleteStatement :binary
+ alias :visit_Arel_Nodes_DoesNotMatch :binary
+ alias :visit_Arel_Nodes_Equality :binary
+ alias :visit_Arel_Nodes_FullOuterJoin :binary
+ alias :visit_Arel_Nodes_GreaterThan :binary
+ alias :visit_Arel_Nodes_GreaterThanOrEqual :binary
+ alias :visit_Arel_Nodes_In :binary
+ alias :visit_Arel_Nodes_InfixOperation :binary
+ alias :visit_Arel_Nodes_JoinSource :binary
+ alias :visit_Arel_Nodes_InnerJoin :binary
+ alias :visit_Arel_Nodes_LessThan :binary
+ alias :visit_Arel_Nodes_LessThanOrEqual :binary
+ alias :visit_Arel_Nodes_Matches :binary
+ alias :visit_Arel_Nodes_NotEqual :binary
+ alias :visit_Arel_Nodes_NotIn :binary
+ alias :visit_Arel_Nodes_NotRegexp :binary
+ alias :visit_Arel_Nodes_IsNotDistinctFrom :binary
+ alias :visit_Arel_Nodes_IsDistinctFrom :binary
+ alias :visit_Arel_Nodes_Or :binary
+ alias :visit_Arel_Nodes_OuterJoin :binary
+ alias :visit_Arel_Nodes_Regexp :binary
+ alias :visit_Arel_Nodes_RightOuterJoin :binary
+ alias :visit_Arel_Nodes_TableAlias :binary
+ alias :visit_Arel_Nodes_Values :binary
+ alias :visit_Arel_Nodes_When :binary
+
+ def visit_Arel_Nodes_StringJoin(o)
+ visit o.left
+ end
+
+ def visit_Arel_Attribute(o)
+ visit o.relation
+ visit o.name
+ end
+ alias :visit_Arel_Attributes_Integer :visit_Arel_Attribute
+ alias :visit_Arel_Attributes_Float :visit_Arel_Attribute
+ alias :visit_Arel_Attributes_String :visit_Arel_Attribute
+ alias :visit_Arel_Attributes_Time :visit_Arel_Attribute
+ alias :visit_Arel_Attributes_Boolean :visit_Arel_Attribute
+ alias :visit_Arel_Attributes_Attribute :visit_Arel_Attribute
+ alias :visit_Arel_Attributes_Decimal :visit_Arel_Attribute
+
+ def visit_Arel_Table(o)
+ visit o.name
+ end
+
+ def terminal(o)
+ end
+ alias :visit_ActiveSupport_Multibyte_Chars :terminal
+ alias :visit_ActiveSupport_StringInquirer :terminal
+ alias :visit_Arel_Nodes_Lock :terminal
+ alias :visit_Arel_Nodes_Node :terminal
+ alias :visit_Arel_Nodes_SqlLiteral :terminal
+ alias :visit_Arel_Nodes_BindParam :terminal
+ alias :visit_Arel_Nodes_Window :terminal
+ alias :visit_Arel_Nodes_True :terminal
+ alias :visit_Arel_Nodes_False :terminal
+ alias :visit_BigDecimal :terminal
+ alias :visit_Class :terminal
+ alias :visit_Date :terminal
+ alias :visit_DateTime :terminal
+ alias :visit_FalseClass :terminal
+ alias :visit_Float :terminal
+ alias :visit_Integer :terminal
+ alias :visit_NilClass :terminal
+ alias :visit_String :terminal
+ alias :visit_Symbol :terminal
+ alias :visit_Time :terminal
+ alias :visit_TrueClass :terminal
+
+ def visit_Arel_Nodes_InsertStatement(o)
+ visit o.relation
+ visit o.columns
+ visit o.values
+ end
+
+ def visit_Arel_Nodes_SelectCore(o)
+ visit o.projections
+ visit o.source
+ visit o.wheres
+ visit o.groups
+ visit o.windows
+ visit o.havings
+ end
+
+ def visit_Arel_Nodes_SelectStatement(o)
+ visit o.cores
+ visit o.orders
+ visit o.limit
+ visit o.lock
+ visit o.offset
+ end
+
+ def visit_Arel_Nodes_UpdateStatement(o)
+ visit o.relation
+ visit o.values
+ visit o.wheres
+ visit o.orders
+ visit o.limit
+ end
+
+ def visit_Array(o)
+ o.each { |i| visit i }
+ end
+ alias :visit_Set :visit_Array
+
+ def visit_Hash(o)
+ o.each { |k, v| visit(k); visit(v) }
+ end
+
+ DISPATCH = dispatch_cache
+
+ def get_dispatch_cache
+ DISPATCH
+ end
+ end
+ end
+end
diff --git a/activerecord/lib/arel/visitors/dot.rb b/activerecord/lib/arel/visitors/dot.rb
new file mode 100644
index 0000000000..6389c875cb
--- /dev/null
+++ b/activerecord/lib/arel/visitors/dot.rb
@@ -0,0 +1,292 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module Visitors
+ class Dot < Arel::Visitors::Visitor
+ class Node # :nodoc:
+ attr_accessor :name, :id, :fields
+
+ def initialize(name, id, fields = [])
+ @name = name
+ @id = id
+ @fields = fields
+ end
+ end
+
+ class Edge < Struct.new :name, :from, :to # :nodoc:
+ end
+
+ def initialize
+ super()
+ @nodes = []
+ @edges = []
+ @node_stack = []
+ @edge_stack = []
+ @seen = {}
+ end
+
+ def accept(object, collector)
+ visit object
+ collector << to_dot
+ end
+
+ private
+
+ def visit_Arel_Nodes_Ordering(o)
+ visit_edge o, "expr"
+ end
+
+ def visit_Arel_Nodes_TableAlias(o)
+ visit_edge o, "name"
+ visit_edge o, "relation"
+ end
+
+ def visit_Arel_Nodes_Count(o)
+ visit_edge o, "expressions"
+ visit_edge o, "distinct"
+ end
+
+ def visit_Arel_Nodes_Values(o)
+ visit_edge o, "expressions"
+ end
+
+ def visit_Arel_Nodes_StringJoin(o)
+ visit_edge o, "left"
+ end
+
+ def visit_Arel_Nodes_InnerJoin(o)
+ visit_edge o, "left"
+ visit_edge o, "right"
+ end
+ alias :visit_Arel_Nodes_FullOuterJoin :visit_Arel_Nodes_InnerJoin
+ alias :visit_Arel_Nodes_OuterJoin :visit_Arel_Nodes_InnerJoin
+ alias :visit_Arel_Nodes_RightOuterJoin :visit_Arel_Nodes_InnerJoin
+
+ def visit_Arel_Nodes_DeleteStatement(o)
+ visit_edge o, "relation"
+ visit_edge o, "wheres"
+ end
+
+ def unary(o)
+ visit_edge o, "expr"
+ end
+ alias :visit_Arel_Nodes_Group :unary
+ alias :visit_Arel_Nodes_Cube :unary
+ alias :visit_Arel_Nodes_RollUp :unary
+ alias :visit_Arel_Nodes_GroupingSet :unary
+ alias :visit_Arel_Nodes_GroupingElement :unary
+ alias :visit_Arel_Nodes_Grouping :unary
+ alias :visit_Arel_Nodes_Having :unary
+ alias :visit_Arel_Nodes_Limit :unary
+ alias :visit_Arel_Nodes_Not :unary
+ alias :visit_Arel_Nodes_Offset :unary
+ alias :visit_Arel_Nodes_On :unary
+ alias :visit_Arel_Nodes_UnqualifiedColumn :unary
+ alias :visit_Arel_Nodes_Preceding :unary
+ alias :visit_Arel_Nodes_Following :unary
+ alias :visit_Arel_Nodes_Rows :unary
+ alias :visit_Arel_Nodes_Range :unary
+
+ def window(o)
+ visit_edge o, "partitions"
+ visit_edge o, "orders"
+ visit_edge o, "framing"
+ end
+ alias :visit_Arel_Nodes_Window :window
+
+ def named_window(o)
+ visit_edge o, "partitions"
+ visit_edge o, "orders"
+ visit_edge o, "framing"
+ visit_edge o, "name"
+ end
+ alias :visit_Arel_Nodes_NamedWindow :named_window
+
+ def function(o)
+ visit_edge o, "expressions"
+ visit_edge o, "distinct"
+ visit_edge o, "alias"
+ end
+ alias :visit_Arel_Nodes_Exists :function
+ alias :visit_Arel_Nodes_Min :function
+ alias :visit_Arel_Nodes_Max :function
+ alias :visit_Arel_Nodes_Avg :function
+ alias :visit_Arel_Nodes_Sum :function
+
+ def extract(o)
+ visit_edge o, "expressions"
+ visit_edge o, "alias"
+ end
+ alias :visit_Arel_Nodes_Extract :extract
+
+ def visit_Arel_Nodes_NamedFunction(o)
+ visit_edge o, "name"
+ visit_edge o, "expressions"
+ visit_edge o, "distinct"
+ visit_edge o, "alias"
+ end
+
+ def visit_Arel_Nodes_InsertStatement(o)
+ visit_edge o, "relation"
+ visit_edge o, "columns"
+ visit_edge o, "values"
+ end
+
+ def visit_Arel_Nodes_SelectCore(o)
+ visit_edge o, "source"
+ visit_edge o, "projections"
+ visit_edge o, "wheres"
+ visit_edge o, "windows"
+ end
+
+ def visit_Arel_Nodes_SelectStatement(o)
+ visit_edge o, "cores"
+ visit_edge o, "limit"
+ visit_edge o, "orders"
+ visit_edge o, "offset"
+ end
+
+ def visit_Arel_Nodes_UpdateStatement(o)
+ visit_edge o, "relation"
+ visit_edge o, "wheres"
+ visit_edge o, "values"
+ end
+
+ def visit_Arel_Table(o)
+ visit_edge o, "name"
+ end
+
+ def visit_Arel_Nodes_Casted(o)
+ visit_edge o, "val"
+ visit_edge o, "attribute"
+ end
+
+ def visit_Arel_Attribute(o)
+ visit_edge o, "relation"
+ visit_edge o, "name"
+ end
+ alias :visit_Arel_Attributes_Integer :visit_Arel_Attribute
+ alias :visit_Arel_Attributes_Float :visit_Arel_Attribute
+ alias :visit_Arel_Attributes_String :visit_Arel_Attribute
+ alias :visit_Arel_Attributes_Time :visit_Arel_Attribute
+ alias :visit_Arel_Attributes_Boolean :visit_Arel_Attribute
+ alias :visit_Arel_Attributes_Attribute :visit_Arel_Attribute
+
+ def nary(o)
+ o.children.each_with_index do |x, i|
+ edge(i) { visit x }
+ end
+ end
+ alias :visit_Arel_Nodes_And :nary
+
+ def binary(o)
+ visit_edge o, "left"
+ visit_edge o, "right"
+ end
+ alias :visit_Arel_Nodes_As :binary
+ alias :visit_Arel_Nodes_Assignment :binary
+ alias :visit_Arel_Nodes_Between :binary
+ alias :visit_Arel_Nodes_Concat :binary
+ alias :visit_Arel_Nodes_DoesNotMatch :binary
+ alias :visit_Arel_Nodes_Equality :binary
+ alias :visit_Arel_Nodes_GreaterThan :binary
+ alias :visit_Arel_Nodes_GreaterThanOrEqual :binary
+ alias :visit_Arel_Nodes_In :binary
+ alias :visit_Arel_Nodes_JoinSource :binary
+ alias :visit_Arel_Nodes_LessThan :binary
+ alias :visit_Arel_Nodes_LessThanOrEqual :binary
+ alias :visit_Arel_Nodes_IsNotDistinctFrom :binary
+ alias :visit_Arel_Nodes_IsDistinctFrom :binary
+ alias :visit_Arel_Nodes_Matches :binary
+ alias :visit_Arel_Nodes_NotEqual :binary
+ alias :visit_Arel_Nodes_NotIn :binary
+ alias :visit_Arel_Nodes_Or :binary
+ alias :visit_Arel_Nodes_Over :binary
+
+ def visit_String(o)
+ @node_stack.last.fields << o
+ end
+ alias :visit_Time :visit_String
+ alias :visit_Date :visit_String
+ alias :visit_DateTime :visit_String
+ alias :visit_NilClass :visit_String
+ alias :visit_TrueClass :visit_String
+ alias :visit_FalseClass :visit_String
+ alias :visit_Integer :visit_String
+ alias :visit_BigDecimal :visit_String
+ alias :visit_Float :visit_String
+ alias :visit_Symbol :visit_String
+ alias :visit_Arel_Nodes_SqlLiteral :visit_String
+
+ def visit_Arel_Nodes_BindParam(o); end
+
+ def visit_Hash(o)
+ o.each_with_index do |pair, i|
+ edge("pair_#{i}") { visit pair }
+ end
+ end
+
+ def visit_Array(o)
+ o.each_with_index do |x, i|
+ edge(i) { visit x }
+ end
+ end
+ alias :visit_Set :visit_Array
+
+ def visit_edge(o, method)
+ edge(method) { visit o.send(method) }
+ end
+
+ def visit(o)
+ if node = @seen[o.object_id]
+ @edge_stack.last.to = node
+ return
+ end
+
+ node = Node.new(o.class.name, o.object_id)
+ @seen[node.id] = node
+ @nodes << node
+ with_node node do
+ super
+ end
+ end
+
+ def edge(name)
+ edge = Edge.new(name, @node_stack.last)
+ @edge_stack.push edge
+ @edges << edge
+ yield
+ @edge_stack.pop
+ end
+
+ def with_node(node)
+ if edge = @edge_stack.last
+ edge.to = node
+ end
+
+ @node_stack.push node
+ yield
+ @node_stack.pop
+ end
+
+ def quote(string)
+ string.to_s.gsub('"', '\"')
+ end
+
+ def to_dot
+ "digraph \"Arel\" {\nnode [width=0.375,height=0.25,shape=record];\n" +
+ @nodes.map { |node|
+ label = "<f0>#{node.name}"
+
+ node.fields.each_with_index do |field, i|
+ label += "|<f#{i + 1}>#{quote field}"
+ end
+
+ "#{node.id} [label=\"#{label}\"];"
+ }.join("\n") + "\n" + @edges.map { |edge|
+ "#{edge.from.id} -> #{edge.to.id} [label=\"#{edge.name}\"];"
+ }.join("\n") + "\n}"
+ end
+ end
+ end
+end
diff --git a/activerecord/lib/arel/visitors/ibm_db.rb b/activerecord/lib/arel/visitors/ibm_db.rb
new file mode 100644
index 0000000000..73166054da
--- /dev/null
+++ b/activerecord/lib/arel/visitors/ibm_db.rb
@@ -0,0 +1,21 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module Visitors
+ class IBM_DB < Arel::Visitors::ToSql
+ private
+
+ def visit_Arel_Nodes_Limit(o, collector)
+ collector << "FETCH FIRST "
+ collector = visit o.expr, collector
+ collector << " ROWS ONLY"
+ end
+
+ def is_distinct_from(o, collector)
+ collector << "DECODE("
+ collector = visit [o.left, o.right, 0, 1], collector
+ collector << ")"
+ end
+ end
+ end
+end
diff --git a/activerecord/lib/arel/visitors/informix.rb b/activerecord/lib/arel/visitors/informix.rb
new file mode 100644
index 0000000000..0a9713794e
--- /dev/null
+++ b/activerecord/lib/arel/visitors/informix.rb
@@ -0,0 +1,55 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module Visitors
+ class Informix < Arel::Visitors::ToSql
+ private
+ def visit_Arel_Nodes_SelectStatement(o, collector)
+ collector << "SELECT "
+ collector = maybe_visit o.offset, collector
+ collector = maybe_visit o.limit, collector
+ collector = o.cores.inject(collector) { |c, x|
+ visit_Arel_Nodes_SelectCore x, c
+ }
+ if o.orders.any?
+ collector << "ORDER BY "
+ collector = inject_join o.orders, collector, ", "
+ end
+ collector = maybe_visit o.lock, collector
+ end
+ def visit_Arel_Nodes_SelectCore(o, collector)
+ collector = inject_join o.projections, collector, ", "
+ if o.source && !o.source.empty?
+ collector << " FROM "
+ collector = visit o.source, collector
+ end
+
+ if o.wheres.any?
+ collector << " WHERE "
+ collector = inject_join o.wheres, collector, " AND "
+ end
+
+ if o.groups.any?
+ collector << "GROUP BY "
+ collector = inject_join o.groups, collector, ", "
+ end
+
+ if o.havings.any?
+ collector << " HAVING "
+ collector = inject_join o.havings, collector, " AND "
+ end
+ collector
+ end
+
+ def visit_Arel_Nodes_Offset(o, collector)
+ collector << "SKIP "
+ visit o.expr, collector
+ end
+ def visit_Arel_Nodes_Limit(o, collector)
+ collector << "FIRST "
+ visit o.expr, collector
+ collector << " "
+ end
+ end
+ end
+end
diff --git a/activerecord/lib/arel/visitors/mssql.rb b/activerecord/lib/arel/visitors/mssql.rb
new file mode 100644
index 0000000000..fdd864b40d
--- /dev/null
+++ b/activerecord/lib/arel/visitors/mssql.rb
@@ -0,0 +1,143 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module Visitors
+ class MSSQL < Arel::Visitors::ToSql
+ RowNumber = Struct.new :children
+
+ def initialize(*)
+ @primary_keys = {}
+ super
+ end
+
+ private
+
+ def visit_Arel_Nodes_IsNotDistinctFrom(o, collector)
+ right = o.right
+
+ if right.nil?
+ collector = visit o.left, collector
+ collector << " IS NULL"
+ else
+ collector << "EXISTS (VALUES ("
+ collector = visit o.left, collector
+ collector << ") INTERSECT VALUES ("
+ collector = visit right, collector
+ collector << "))"
+ end
+ end
+
+ def visit_Arel_Nodes_IsDistinctFrom(o, collector)
+ if o.right.nil?
+ collector = visit o.left, collector
+ collector << " IS NOT NULL"
+ else
+ collector << "NOT "
+ visit_Arel_Nodes_IsNotDistinctFrom o, collector
+ end
+ end
+
+ def visit_Arel_Visitors_MSSQL_RowNumber(o, collector)
+ collector << "ROW_NUMBER() OVER (ORDER BY "
+ inject_join(o.children, collector, ", ") << ") as _row_num"
+ end
+
+ def visit_Arel_Nodes_SelectStatement(o, collector)
+ if !o.limit && !o.offset
+ return super
+ end
+
+ is_select_count = false
+ o.cores.each { |x|
+ core_order_by = row_num_literal determine_order_by(o.orders, x)
+ if select_count? x
+ x.projections = [core_order_by]
+ is_select_count = true
+ else
+ x.projections << core_order_by
+ end
+ }
+
+ if is_select_count
+ # fixme count distinct wouldn't work with limit or offset
+ collector << "SELECT COUNT(1) as count_id FROM ("
+ end
+
+ collector << "SELECT _t.* FROM ("
+ collector = o.cores.inject(collector) { |c, x|
+ visit_Arel_Nodes_SelectCore x, c
+ }
+ collector << ") as _t WHERE #{get_offset_limit_clause(o)}"
+
+ if is_select_count
+ collector << ") AS subquery"
+ else
+ collector
+ end
+ end
+
+ def get_offset_limit_clause(o)
+ first_row = o.offset ? o.offset.expr.to_i + 1 : 1
+ last_row = o.limit ? o.limit.expr.to_i - 1 + first_row : nil
+ if last_row
+ " _row_num BETWEEN #{first_row} AND #{last_row}"
+ else
+ " _row_num >= #{first_row}"
+ end
+ end
+
+ def visit_Arel_Nodes_DeleteStatement(o, collector)
+ collector << "DELETE "
+ if o.limit
+ collector << "TOP ("
+ visit o.limit.expr, collector
+ collector << ") "
+ end
+ collector << "FROM "
+ collector = visit o.relation, collector
+ if o.wheres.any?
+ collector << " WHERE "
+ inject_join o.wheres, collector, AND
+ else
+ collector
+ end
+ end
+
+ def determine_order_by(orders, x)
+ if orders.any?
+ orders
+ elsif x.groups.any?
+ x.groups
+ else
+ pk = find_left_table_pk(x.froms)
+ pk ? [pk] : []
+ end
+ end
+
+ def row_num_literal(order_by)
+ RowNumber.new order_by
+ end
+
+ def select_count?(x)
+ x.projections.length == 1 && Arel::Nodes::Count === x.projections.first
+ end
+
+ # FIXME raise exception of there is no pk?
+ def find_left_table_pk(o)
+ if o.kind_of?(Arel::Nodes::Join)
+ find_left_table_pk(o.left)
+ elsif o.instance_of?(Arel::Table)
+ find_primary_key(o)
+ end
+ end
+
+ def find_primary_key(o)
+ @primary_keys[o.name] ||= begin
+ primary_key_name = @connection.primary_key(o.name)
+ # some tables might be without primary key
+ primary_key_name && o[primary_key_name]
+ end
+ end
+ end
+ end
+end
diff --git a/activerecord/lib/arel/visitors/mysql.rb b/activerecord/lib/arel/visitors/mysql.rb
new file mode 100644
index 0000000000..dd77cfdf66
--- /dev/null
+++ b/activerecord/lib/arel/visitors/mysql.rb
@@ -0,0 +1,83 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module Visitors
+ class MySQL < Arel::Visitors::ToSql
+ private
+ def visit_Arel_Nodes_Bin(o, collector)
+ collector << "BINARY "
+ visit o.expr, collector
+ end
+
+ def visit_Arel_Nodes_UnqualifiedColumn(o, collector)
+ visit o.expr, collector
+ end
+
+ ###
+ # :'(
+ # http://dev.mysql.com/doc/refman/5.0/en/select.html#id3482214
+ def visit_Arel_Nodes_SelectStatement(o, collector)
+ if o.offset && !o.limit
+ o.limit = Arel::Nodes::Limit.new(18446744073709551615)
+ end
+ super
+ end
+
+ def visit_Arel_Nodes_SelectCore(o, collector)
+ o.froms ||= Arel.sql("DUAL")
+ super
+ end
+
+ def visit_Arel_Nodes_Concat(o, collector)
+ collector << " CONCAT("
+ visit o.left, collector
+ collector << ", "
+ visit o.right, collector
+ collector << ") "
+ collector
+ end
+
+ def visit_Arel_Nodes_IsNotDistinctFrom(o, collector)
+ collector = visit o.left, collector
+ collector << " <=> "
+ visit o.right, collector
+ end
+
+ def visit_Arel_Nodes_IsDistinctFrom(o, collector)
+ collector << "NOT "
+ visit_Arel_Nodes_IsNotDistinctFrom o, collector
+ end
+
+ # In the simple case, MySQL allows us to place JOINs directly into the UPDATE
+ # query. However, this does not allow for LIMIT, OFFSET and ORDER. To support
+ # these, we must use a subquery.
+ def prepare_update_statement(o)
+ if o.offset || has_join_sources?(o) && has_limit_or_offset_or_orders?(o)
+ super
+ else
+ o
+ end
+ end
+ alias :prepare_delete_statement :prepare_update_statement
+
+ # MySQL is too stupid to create a temporary table for use subquery, so we have
+ # to give it some prompting in the form of a subsubquery.
+ def build_subselect(key, o)
+ subselect = super
+
+ # Materialize subquery by adding distinct
+ # to work with MySQL 5.7.6 which sets optimizer_switch='derived_merge=on'
+ unless has_limit_or_offset_or_orders?(subselect)
+ core = subselect.cores.last
+ core.set_quantifier = Arel::Nodes::Distinct.new
+ end
+
+ Nodes::SelectStatement.new.tap do |stmt|
+ core = stmt.cores.last
+ core.froms = Nodes::Grouping.new(subselect).as("__active_record_temp")
+ core.projections = [Arel.sql(quote_column_name(key.name))]
+ end
+ end
+ end
+ end
+end
diff --git a/activerecord/lib/arel/visitors/oracle.rb b/activerecord/lib/arel/visitors/oracle.rb
new file mode 100644
index 0000000000..f96bf65ee5
--- /dev/null
+++ b/activerecord/lib/arel/visitors/oracle.rb
@@ -0,0 +1,159 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module Visitors
+ class Oracle < Arel::Visitors::ToSql
+ private
+
+ def visit_Arel_Nodes_SelectStatement(o, collector)
+ o = order_hacks(o)
+
+ # if need to select first records without ORDER BY and GROUP BY and without DISTINCT
+ # then can use simple ROWNUM in WHERE clause
+ if o.limit && o.orders.empty? && o.cores.first.groups.empty? && !o.offset && o.cores.first.set_quantifier.class.to_s !~ /Distinct/
+ o.cores.last.wheres.push Nodes::LessThanOrEqual.new(
+ Nodes::SqlLiteral.new("ROWNUM"), o.limit.expr
+ )
+ return super
+ end
+
+ if o.limit && o.offset
+ o = o.dup
+ limit = o.limit.expr
+ offset = o.offset
+ o.offset = nil
+ collector << "
+ SELECT * FROM (
+ SELECT raw_sql_.*, rownum raw_rnum_
+ FROM ("
+
+ collector = super(o, collector)
+
+ if offset.expr.is_a? Nodes::BindParam
+ collector << ") raw_sql_ WHERE rownum <= ("
+ collector = visit offset.expr, collector
+ collector << " + "
+ collector = visit limit, collector
+ collector << ") ) WHERE raw_rnum_ > "
+ collector = visit offset.expr, collector
+ return collector
+ else
+ collector << ") raw_sql_
+ WHERE rownum <= #{offset.expr.to_i + limit}
+ )
+ WHERE "
+ return visit(offset, collector)
+ end
+ end
+
+ if o.limit
+ o = o.dup
+ limit = o.limit.expr
+ collector << "SELECT * FROM ("
+ collector = super(o, collector)
+ collector << ") WHERE ROWNUM <= "
+ return visit limit, collector
+ end
+
+ if o.offset
+ o = o.dup
+ offset = o.offset
+ o.offset = nil
+ collector << "SELECT * FROM (
+ SELECT raw_sql_.*, rownum raw_rnum_
+ FROM ("
+ collector = super(o, collector)
+ collector << ") raw_sql_
+ )
+ WHERE "
+ return visit offset, collector
+ end
+
+ super
+ end
+
+ def visit_Arel_Nodes_Limit(o, collector)
+ collector
+ end
+
+ def visit_Arel_Nodes_Offset(o, collector)
+ collector << "raw_rnum_ > "
+ visit o.expr, collector
+ end
+
+ def visit_Arel_Nodes_Except(o, collector)
+ collector << "( "
+ collector = infix_value o, collector, " MINUS "
+ collector << " )"
+ end
+
+ def visit_Arel_Nodes_UpdateStatement(o, collector)
+ # Oracle does not allow ORDER BY/LIMIT in UPDATEs.
+ if o.orders.any? && o.limit.nil?
+ # However, there is no harm in silently eating the ORDER BY clause if no LIMIT has been provided,
+ # otherwise let the user deal with the error
+ o = o.dup
+ o.orders = []
+ end
+
+ super
+ end
+
+ ###
+ # Hacks for the order clauses specific to Oracle
+ def order_hacks(o)
+ return o if o.orders.empty?
+ return o unless o.cores.any? do |core|
+ core.projections.any? do |projection|
+ /FIRST_VALUE/ === projection
+ end
+ end
+ # Previous version with join and split broke ORDER BY clause
+ # if it contained functions with several arguments (separated by ',').
+ #
+ # orders = o.orders.map { |x| visit x }.join(', ').split(',')
+ orders = o.orders.map do |x|
+ string = visit(x, Arel::Collectors::SQLString.new).value
+ if string.include?(",")
+ split_order_string(string)
+ else
+ string
+ end
+ end.flatten
+ o.orders = []
+ orders.each_with_index do |order, i|
+ o.orders <<
+ Nodes::SqlLiteral.new("alias_#{i}__#{' DESC' if /\bdesc$/i === order}")
+ end
+ o
+ end
+
+ # Split string by commas but count opening and closing brackets
+ # and ignore commas inside brackets.
+ def split_order_string(string)
+ array = []
+ i = 0
+ string.split(",").each do |part|
+ if array[i]
+ array[i] << "," << part
+ else
+ # to ensure that array[i] will be String and not Arel::Nodes::SqlLiteral
+ array[i] = part.to_s
+ end
+ i += 1 if array[i].count("(") == array[i].count(")")
+ end
+ array
+ end
+
+ def visit_Arel_Nodes_BindParam(o, collector)
+ collector.add_bind(o.value) { |i| ":a#{i}" }
+ end
+
+ def is_distinct_from(o, collector)
+ collector << "DECODE("
+ collector = visit [o.left, o.right, 0, 1], collector
+ collector << ")"
+ end
+ end
+ end
+end
diff --git a/activerecord/lib/arel/visitors/oracle12.rb b/activerecord/lib/arel/visitors/oracle12.rb
new file mode 100644
index 0000000000..b092aa95e0
--- /dev/null
+++ b/activerecord/lib/arel/visitors/oracle12.rb
@@ -0,0 +1,67 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module Visitors
+ class Oracle12 < Arel::Visitors::ToSql
+ private
+
+ def visit_Arel_Nodes_SelectStatement(o, collector)
+ # Oracle does not allow LIMIT clause with select for update
+ if o.limit && o.lock
+ raise ArgumentError, <<-MSG
+ 'Combination of limit and lock is not supported.
+ because generated SQL statements
+ `SELECT FOR UPDATE and FETCH FIRST n ROWS` generates ORA-02014.`
+ MSG
+ end
+ super
+ end
+
+ def visit_Arel_Nodes_SelectOptions(o, collector)
+ collector = maybe_visit o.offset, collector
+ collector = maybe_visit o.limit, collector
+ collector = maybe_visit o.lock, collector
+ end
+
+ def visit_Arel_Nodes_Limit(o, collector)
+ collector << "FETCH FIRST "
+ collector = visit o.expr, collector
+ collector << " ROWS ONLY"
+ end
+
+ def visit_Arel_Nodes_Offset(o, collector)
+ collector << "OFFSET "
+ visit o.expr, collector
+ collector << " ROWS"
+ end
+
+ def visit_Arel_Nodes_Except(o, collector)
+ collector << "( "
+ collector = infix_value o, collector, " MINUS "
+ collector << " )"
+ end
+
+ def visit_Arel_Nodes_UpdateStatement(o, collector)
+ # Oracle does not allow ORDER BY/LIMIT in UPDATEs.
+ if o.orders.any? && o.limit.nil?
+ # However, there is no harm in silently eating the ORDER BY clause if no LIMIT has been provided,
+ # otherwise let the user deal with the error
+ o = o.dup
+ o.orders = []
+ end
+
+ super
+ end
+
+ def visit_Arel_Nodes_BindParam(o, collector)
+ collector.add_bind(o.value) { |i| ":a#{i}" }
+ end
+
+ def is_distinct_from(o, collector)
+ collector << "DECODE("
+ collector = visit [o.left, o.right, 0, 1], collector
+ collector << ")"
+ end
+ end
+ end
+end
diff --git a/activerecord/lib/arel/visitors/postgresql.rb b/activerecord/lib/arel/visitors/postgresql.rb
new file mode 100644
index 0000000000..920776b4dc
--- /dev/null
+++ b/activerecord/lib/arel/visitors/postgresql.rb
@@ -0,0 +1,116 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module Visitors
+ class PostgreSQL < Arel::Visitors::ToSql
+ CUBE = "CUBE"
+ ROLLUP = "ROLLUP"
+ GROUPING_SETS = "GROUPING SETS"
+ LATERAL = "LATERAL"
+
+ private
+
+ def visit_Arel_Nodes_Matches(o, collector)
+ op = o.case_sensitive ? " LIKE " : " ILIKE "
+ collector = infix_value o, collector, op
+ if o.escape
+ collector << " ESCAPE "
+ visit o.escape, collector
+ else
+ collector
+ end
+ end
+
+ def visit_Arel_Nodes_DoesNotMatch(o, collector)
+ op = o.case_sensitive ? " NOT LIKE " : " NOT ILIKE "
+ collector = infix_value o, collector, op
+ if o.escape
+ collector << " ESCAPE "
+ visit o.escape, collector
+ else
+ collector
+ end
+ end
+
+ def visit_Arel_Nodes_Regexp(o, collector)
+ op = o.case_sensitive ? " ~ " : " ~* "
+ infix_value o, collector, op
+ end
+
+ def visit_Arel_Nodes_NotRegexp(o, collector)
+ op = o.case_sensitive ? " !~ " : " !~* "
+ infix_value o, collector, op
+ end
+
+ def visit_Arel_Nodes_DistinctOn(o, collector)
+ collector << "DISTINCT ON ( "
+ visit(o.expr, collector) << " )"
+ end
+
+ def visit_Arel_Nodes_BindParam(o, collector)
+ collector.add_bind(o.value) { |i| "$#{i}" }
+ end
+
+ def visit_Arel_Nodes_GroupingElement(o, collector)
+ collector << "( "
+ visit(o.expr, collector) << " )"
+ end
+
+ def visit_Arel_Nodes_Cube(o, collector)
+ collector << CUBE
+ grouping_array_or_grouping_element o, collector
+ end
+
+ def visit_Arel_Nodes_RollUp(o, collector)
+ collector << ROLLUP
+ grouping_array_or_grouping_element o, collector
+ end
+
+ def visit_Arel_Nodes_GroupingSet(o, collector)
+ collector << GROUPING_SETS
+ grouping_array_or_grouping_element o, collector
+ end
+
+ def visit_Arel_Nodes_Lateral(o, collector)
+ collector << LATERAL
+ collector << SPACE
+ grouping_parentheses o, collector
+ end
+
+ def visit_Arel_Nodes_IsNotDistinctFrom(o, collector)
+ collector = visit o.left, collector
+ collector << " IS NOT DISTINCT FROM "
+ visit o.right, collector
+ end
+
+ def visit_Arel_Nodes_IsDistinctFrom(o, collector)
+ collector = visit o.left, collector
+ collector << " IS DISTINCT FROM "
+ visit o.right, collector
+ end
+
+ # Used by Lateral visitor to enclose select queries in parentheses
+ def grouping_parentheses(o, collector)
+ if o.expr.is_a? Nodes::SelectStatement
+ collector << "("
+ visit o.expr, collector
+ collector << ")"
+ else
+ visit o.expr, collector
+ end
+ end
+
+ # Utilized by GroupingSet, Cube & RollUp visitors to
+ # handle grouping aggregation semantics
+ def grouping_array_or_grouping_element(o, collector)
+ if o.expr.is_a? Array
+ collector << "( "
+ visit o.expr, collector
+ collector << " )"
+ else
+ visit o.expr, collector
+ end
+ end
+ end
+ end
+end
diff --git a/activerecord/lib/arel/visitors/sqlite.rb b/activerecord/lib/arel/visitors/sqlite.rb
new file mode 100644
index 0000000000..af6f7e856a
--- /dev/null
+++ b/activerecord/lib/arel/visitors/sqlite.rb
@@ -0,0 +1,39 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module Visitors
+ class SQLite < Arel::Visitors::ToSql
+ private
+
+ # Locks are not supported in SQLite
+ def visit_Arel_Nodes_Lock(o, collector)
+ collector
+ end
+
+ def visit_Arel_Nodes_SelectStatement(o, collector)
+ o.limit = Arel::Nodes::Limit.new(-1) if o.offset && !o.limit
+ super
+ end
+
+ def visit_Arel_Nodes_True(o, collector)
+ collector << "1"
+ end
+
+ def visit_Arel_Nodes_False(o, collector)
+ collector << "0"
+ end
+
+ def visit_Arel_Nodes_IsNotDistinctFrom(o, collector)
+ collector = visit o.left, collector
+ collector << " IS "
+ visit o.right, collector
+ end
+
+ def visit_Arel_Nodes_IsDistinctFrom(o, collector)
+ collector = visit o.left, collector
+ collector << " IS NOT "
+ visit o.right, collector
+ end
+ end
+ end
+end
diff --git a/activerecord/lib/arel/visitors/to_sql.rb b/activerecord/lib/arel/visitors/to_sql.rb
new file mode 100644
index 0000000000..f9fe4404eb
--- /dev/null
+++ b/activerecord/lib/arel/visitors/to_sql.rb
@@ -0,0 +1,911 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module Visitors
+ class UnsupportedVisitError < StandardError
+ def initialize(object)
+ super "Unsupported argument type: #{object.class.name}. Construct an Arel node instead."
+ end
+ end
+
+ class ToSql < Arel::Visitors::Visitor
+ ##
+ # This is some roflscale crazy stuff. I'm roflscaling this because
+ # building SQL queries is a hotspot. I will explain the roflscale so that
+ # others will not rm this code.
+ #
+ # In YARV, string literals in a method body will get duped when the byte
+ # code is executed. Let's take a look:
+ #
+ # > puts RubyVM::InstructionSequence.new('def foo; "bar"; end').disasm
+ #
+ # == disasm: <RubyVM::InstructionSequence:foo@<compiled>>=====
+ # 0000 trace 8
+ # 0002 trace 1
+ # 0004 putstring "bar"
+ # 0006 trace 16
+ # 0008 leave
+ #
+ # The `putstring` bytecode will dup the string and push it on the stack.
+ # In many cases in our SQL visitor, that string is never mutated, so there
+ # is no need to dup the literal.
+ #
+ # If we change to a constant lookup, the string will not be duped, and we
+ # can reduce the objects in our system:
+ #
+ # > puts RubyVM::InstructionSequence.new('BAR = "bar"; def foo; BAR; end').disasm
+ #
+ # == disasm: <RubyVM::InstructionSequence:foo@<compiled>>========
+ # 0000 trace 8
+ # 0002 trace 1
+ # 0004 getinlinecache 11, <ic:0>
+ # 0007 getconstant :BAR
+ # 0009 setinlinecache <ic:0>
+ # 0011 trace 16
+ # 0013 leave
+ #
+ # `getconstant` should be a hash lookup, and no object is duped when the
+ # value of the constant is pushed on the stack. Hence the crazy
+ # constants below.
+ #
+ # `matches` and `doesNotMatch` operate case-insensitively via Visitor subclasses
+ # specialized for specific databases when necessary.
+ #
+
+ WHERE = " WHERE " # :nodoc:
+ SPACE = " " # :nodoc:
+ COMMA = ", " # :nodoc:
+ GROUP_BY = " GROUP BY " # :nodoc:
+ ORDER_BY = " ORDER BY " # :nodoc:
+ WINDOW = " WINDOW " # :nodoc:
+ AND = " AND " # :nodoc:
+
+ DISTINCT = "DISTINCT" # :nodoc:
+
+ def initialize(connection)
+ super()
+ @connection = connection
+ end
+
+ def compile(node, collector = Arel::Collectors::SQLString.new)
+ accept(node, collector).value
+ end
+
+ private
+
+ def visit_Arel_Nodes_DeleteStatement(o, collector)
+ o = prepare_delete_statement(o)
+
+ if has_join_sources?(o)
+ collector << "DELETE "
+ visit o.relation.left, collector
+ collector << " FROM "
+ else
+ collector << "DELETE FROM "
+ end
+ collector = visit o.relation, collector
+
+ collect_nodes_for o.wheres, collector, " WHERE ", " AND "
+ collect_nodes_for o.orders, collector, " ORDER BY "
+ maybe_visit o.limit, collector
+ end
+
+ def visit_Arel_Nodes_UpdateStatement(o, collector)
+ o = prepare_update_statement(o)
+
+ collector << "UPDATE "
+ collector = visit o.relation, collector
+ collect_nodes_for o.values, collector, " SET "
+
+ collect_nodes_for o.wheres, collector, " WHERE ", " AND "
+ collect_nodes_for o.orders, collector, " ORDER BY "
+ maybe_visit o.limit, collector
+ end
+
+ def visit_Arel_Nodes_InsertStatement(o, collector)
+ collector << "INSERT INTO "
+ collector = visit o.relation, collector
+ if o.columns.any?
+ collector << " (#{o.columns.map { |x|
+ quote_column_name x.name
+ }.join ', '})"
+ end
+
+ if o.values
+ maybe_visit o.values, collector
+ elsif o.select
+ maybe_visit o.select, collector
+ else
+ collector
+ end
+ end
+
+ def visit_Arel_Nodes_Exists(o, collector)
+ collector << "EXISTS ("
+ collector = visit(o.expressions, collector) << ")"
+ if o.alias
+ collector << " AS "
+ visit o.alias, collector
+ else
+ collector
+ end
+ end
+
+ def visit_Arel_Nodes_Casted(o, collector)
+ collector << quoted(o.val, o.attribute).to_s
+ end
+
+ def visit_Arel_Nodes_Quoted(o, collector)
+ collector << quoted(o.expr, nil).to_s
+ end
+
+ def visit_Arel_Nodes_True(o, collector)
+ collector << "TRUE"
+ end
+
+ def visit_Arel_Nodes_False(o, collector)
+ collector << "FALSE"
+ end
+
+ def visit_Arel_Nodes_ValuesList(o, collector)
+ collector << "VALUES "
+
+ len = o.rows.length - 1
+ o.rows.each_with_index { |row, i|
+ collector << "("
+ row_len = row.length - 1
+ row.each_with_index do |value, k|
+ case value
+ when Nodes::SqlLiteral, Nodes::BindParam
+ collector = visit(value, collector)
+ else
+ collector << quote(value)
+ end
+ collector << COMMA unless k == row_len
+ end
+ collector << ")"
+ collector << COMMA unless i == len
+ }
+ collector
+ end
+
+ def visit_Arel_Nodes_Values(o, collector)
+ collector << "VALUES ("
+
+ len = o.expressions.length - 1
+ o.expressions.each_with_index { |value, i|
+ case value
+ when Nodes::SqlLiteral, Nodes::BindParam
+ collector = visit value, collector
+ else
+ collector << quote(value).to_s
+ end
+ unless i == len
+ collector << COMMA
+ end
+ }
+
+ collector << ")"
+ end
+
+ def visit_Arel_Nodes_SelectStatement(o, collector)
+ if o.with
+ collector = visit o.with, collector
+ collector << SPACE
+ end
+
+ collector = o.cores.inject(collector) { |c, x|
+ visit_Arel_Nodes_SelectCore(x, c)
+ }
+
+ unless o.orders.empty?
+ collector << ORDER_BY
+ len = o.orders.length - 1
+ o.orders.each_with_index { |x, i|
+ collector = visit(x, collector)
+ collector << COMMA unless len == i
+ }
+ end
+
+ visit_Arel_Nodes_SelectOptions(o, collector)
+
+ collector
+ end
+
+ def visit_Arel_Nodes_SelectOptions(o, collector)
+ collector = maybe_visit o.limit, collector
+ collector = maybe_visit o.offset, collector
+ collector = maybe_visit o.lock, collector
+ end
+
+ def visit_Arel_Nodes_SelectCore(o, collector)
+ collector << "SELECT"
+
+ collector = maybe_visit o.set_quantifier, collector
+
+ collect_nodes_for o.projections, collector, SPACE
+
+ if o.source && !o.source.empty?
+ collector << " FROM "
+ collector = visit o.source, collector
+ end
+
+ collect_nodes_for o.wheres, collector, WHERE, AND
+ collect_nodes_for o.groups, collector, GROUP_BY
+ collect_nodes_for o.havings, collector, " HAVING ", AND
+ collect_nodes_for o.windows, collector, WINDOW
+
+ collector
+ end
+
+ def collect_nodes_for(nodes, collector, spacer, connector = COMMA)
+ unless nodes.empty?
+ collector << spacer
+ inject_join nodes, collector, connector
+ end
+ end
+
+ def visit_Arel_Nodes_Bin(o, collector)
+ visit o.expr, collector
+ end
+
+ def visit_Arel_Nodes_Distinct(o, collector)
+ collector << DISTINCT
+ end
+
+ def visit_Arel_Nodes_DistinctOn(o, collector)
+ raise NotImplementedError, "DISTINCT ON not implemented for this db"
+ end
+
+ def visit_Arel_Nodes_With(o, collector)
+ collector << "WITH "
+ inject_join o.children, collector, COMMA
+ end
+
+ def visit_Arel_Nodes_WithRecursive(o, collector)
+ collector << "WITH RECURSIVE "
+ inject_join o.children, collector, COMMA
+ end
+
+ def visit_Arel_Nodes_Union(o, collector)
+ infix_value_with_paren(o, collector, " UNION ")
+ end
+
+ def visit_Arel_Nodes_UnionAll(o, collector)
+ infix_value_with_paren(o, collector, " UNION ALL ")
+ end
+
+ def visit_Arel_Nodes_Intersect(o, collector)
+ collector << "( "
+ infix_value(o, collector, " INTERSECT ") << " )"
+ end
+
+ def visit_Arel_Nodes_Except(o, collector)
+ collector << "( "
+ infix_value(o, collector, " EXCEPT ") << " )"
+ end
+
+ def visit_Arel_Nodes_NamedWindow(o, collector)
+ collector << quote_column_name(o.name)
+ collector << " AS "
+ visit_Arel_Nodes_Window o, collector
+ end
+
+ def visit_Arel_Nodes_Window(o, collector)
+ collector << "("
+
+ collect_nodes_for o.partitions, collector, "PARTITION BY "
+
+ if o.orders.any?
+ collector << SPACE if o.partitions.any?
+ collector << "ORDER BY "
+ collector = inject_join o.orders, collector, ", "
+ end
+
+ if o.framing
+ collector << SPACE if o.partitions.any? || o.orders.any?
+ collector = visit o.framing, collector
+ end
+
+ collector << ")"
+ end
+
+ def visit_Arel_Nodes_Rows(o, collector)
+ if o.expr
+ collector << "ROWS "
+ visit o.expr, collector
+ else
+ collector << "ROWS"
+ end
+ end
+
+ def visit_Arel_Nodes_Range(o, collector)
+ if o.expr
+ collector << "RANGE "
+ visit o.expr, collector
+ else
+ collector << "RANGE"
+ end
+ end
+
+ def visit_Arel_Nodes_Preceding(o, collector)
+ collector = if o.expr
+ visit o.expr, collector
+ else
+ collector << "UNBOUNDED"
+ end
+
+ collector << " PRECEDING"
+ end
+
+ def visit_Arel_Nodes_Following(o, collector)
+ collector = if o.expr
+ visit o.expr, collector
+ else
+ collector << "UNBOUNDED"
+ end
+
+ collector << " FOLLOWING"
+ end
+
+ def visit_Arel_Nodes_CurrentRow(o, collector)
+ collector << "CURRENT ROW"
+ end
+
+ def visit_Arel_Nodes_Over(o, collector)
+ case o.right
+ when nil
+ visit(o.left, collector) << " OVER ()"
+ when Arel::Nodes::SqlLiteral
+ infix_value o, collector, " OVER "
+ when String, Symbol
+ visit(o.left, collector) << " OVER #{quote_column_name o.right.to_s}"
+ else
+ infix_value o, collector, " OVER "
+ end
+ end
+
+ def visit_Arel_Nodes_Offset(o, collector)
+ collector << "OFFSET "
+ visit o.expr, collector
+ end
+
+ def visit_Arel_Nodes_Limit(o, collector)
+ collector << "LIMIT "
+ visit o.expr, collector
+ end
+
+ def visit_Arel_Nodes_Lock(o, collector)
+ visit o.expr, collector
+ end
+
+ def visit_Arel_Nodes_Grouping(o, collector)
+ if o.expr.is_a? Nodes::Grouping
+ visit(o.expr, collector)
+ else
+ collector << "("
+ visit(o.expr, collector) << ")"
+ end
+ end
+
+ def visit_Arel_SelectManager(o, collector)
+ collector << "("
+ visit(o.ast, collector) << ")"
+ end
+
+ def visit_Arel_Nodes_Ascending(o, collector)
+ visit(o.expr, collector) << " ASC"
+ end
+
+ def visit_Arel_Nodes_Descending(o, collector)
+ visit(o.expr, collector) << " DESC"
+ end
+
+ def visit_Arel_Nodes_Group(o, collector)
+ visit o.expr, collector
+ end
+
+ def visit_Arel_Nodes_NamedFunction(o, collector)
+ collector << o.name
+ collector << "("
+ collector << "DISTINCT " if o.distinct
+ collector = inject_join(o.expressions, collector, ", ") << ")"
+ if o.alias
+ collector << " AS "
+ visit o.alias, collector
+ else
+ collector
+ end
+ end
+
+ def visit_Arel_Nodes_Extract(o, collector)
+ collector << "EXTRACT(#{o.field.to_s.upcase} FROM "
+ visit(o.expr, collector) << ")"
+ end
+
+ def visit_Arel_Nodes_Count(o, collector)
+ aggregate "COUNT", o, collector
+ end
+
+ def visit_Arel_Nodes_Sum(o, collector)
+ aggregate "SUM", o, collector
+ end
+
+ def visit_Arel_Nodes_Max(o, collector)
+ aggregate "MAX", o, collector
+ end
+
+ def visit_Arel_Nodes_Min(o, collector)
+ aggregate "MIN", o, collector
+ end
+
+ def visit_Arel_Nodes_Avg(o, collector)
+ aggregate "AVG", o, collector
+ end
+
+ def visit_Arel_Nodes_TableAlias(o, collector)
+ collector = visit o.relation, collector
+ collector << " "
+ collector << quote_table_name(o.name)
+ end
+
+ def visit_Arel_Nodes_Between(o, collector)
+ collector = visit o.left, collector
+ collector << " BETWEEN "
+ visit o.right, collector
+ end
+
+ def visit_Arel_Nodes_GreaterThanOrEqual(o, collector)
+ collector = visit o.left, collector
+ collector << " >= "
+ visit o.right, collector
+ end
+
+ def visit_Arel_Nodes_GreaterThan(o, collector)
+ collector = visit o.left, collector
+ collector << " > "
+ visit o.right, collector
+ end
+
+ def visit_Arel_Nodes_LessThanOrEqual(o, collector)
+ collector = visit o.left, collector
+ collector << " <= "
+ visit o.right, collector
+ end
+
+ def visit_Arel_Nodes_LessThan(o, collector)
+ collector = visit o.left, collector
+ collector << " < "
+ visit o.right, collector
+ end
+
+ def visit_Arel_Nodes_Matches(o, collector)
+ collector = visit o.left, collector
+ collector << " LIKE "
+ collector = visit o.right, collector
+ if o.escape
+ collector << " ESCAPE "
+ visit o.escape, collector
+ else
+ collector
+ end
+ end
+
+ def visit_Arel_Nodes_DoesNotMatch(o, collector)
+ collector = visit o.left, collector
+ collector << " NOT LIKE "
+ collector = visit o.right, collector
+ if o.escape
+ collector << " ESCAPE "
+ visit o.escape, collector
+ else
+ collector
+ end
+ end
+
+ def visit_Arel_Nodes_JoinSource(o, collector)
+ if o.left
+ collector = visit o.left, collector
+ end
+ if o.right.any?
+ collector << SPACE if o.left
+ collector = inject_join o.right, collector, SPACE
+ end
+ collector
+ end
+
+ def visit_Arel_Nodes_Regexp(o, collector)
+ raise NotImplementedError, "~ not implemented for this db"
+ end
+
+ def visit_Arel_Nodes_NotRegexp(o, collector)
+ raise NotImplementedError, "!~ not implemented for this db"
+ end
+
+ def visit_Arel_Nodes_StringJoin(o, collector)
+ visit o.left, collector
+ end
+
+ def visit_Arel_Nodes_FullOuterJoin(o, collector)
+ collector << "FULL OUTER JOIN "
+ collector = visit o.left, collector
+ collector << SPACE
+ visit o.right, collector
+ end
+
+ def visit_Arel_Nodes_OuterJoin(o, collector)
+ collector << "LEFT OUTER JOIN "
+ collector = visit o.left, collector
+ collector << " "
+ visit o.right, collector
+ end
+
+ def visit_Arel_Nodes_RightOuterJoin(o, collector)
+ collector << "RIGHT OUTER JOIN "
+ collector = visit o.left, collector
+ collector << SPACE
+ visit o.right, collector
+ end
+
+ def visit_Arel_Nodes_InnerJoin(o, collector)
+ collector << "INNER JOIN "
+ collector = visit o.left, collector
+ if o.right
+ collector << SPACE
+ visit(o.right, collector)
+ else
+ collector
+ end
+ end
+
+ def visit_Arel_Nodes_On(o, collector)
+ collector << "ON "
+ visit o.expr, collector
+ end
+
+ def visit_Arel_Nodes_Not(o, collector)
+ collector << "NOT ("
+ visit(o.expr, collector) << ")"
+ end
+
+ def visit_Arel_Table(o, collector)
+ if o.table_alias
+ collector << "#{quote_table_name o.name} #{quote_table_name o.table_alias}"
+ else
+ collector << quote_table_name(o.name)
+ end
+ end
+
+ def visit_Arel_Nodes_In(o, collector)
+ if Array === o.right && !o.right.empty?
+ o.right.keep_if { |value| boundable?(value) }
+ end
+
+ if Array === o.right && o.right.empty?
+ collector << "1=0"
+ else
+ collector = visit o.left, collector
+ collector << " IN ("
+ visit(o.right, collector) << ")"
+ end
+ end
+
+ def visit_Arel_Nodes_NotIn(o, collector)
+ if Array === o.right && !o.right.empty?
+ o.right.keep_if { |value| boundable?(value) }
+ end
+
+ if Array === o.right && o.right.empty?
+ collector << "1=1"
+ else
+ collector = visit o.left, collector
+ collector << " NOT IN ("
+ collector = visit o.right, collector
+ collector << ")"
+ end
+ end
+
+ def visit_Arel_Nodes_And(o, collector)
+ inject_join o.children, collector, " AND "
+ end
+
+ def visit_Arel_Nodes_Or(o, collector)
+ collector = visit o.left, collector
+ collector << " OR "
+ visit o.right, collector
+ end
+
+ def visit_Arel_Nodes_Assignment(o, collector)
+ case o.right
+ when Arel::Nodes::Node, Arel::Attributes::Attribute
+ collector = visit o.left, collector
+ collector << " = "
+ visit o.right, collector
+ else
+ collector = visit o.left, collector
+ collector << " = "
+ collector << quote(o.right).to_s
+ end
+ end
+
+ def visit_Arel_Nodes_Equality(o, collector)
+ right = o.right
+
+ collector = visit o.left, collector
+
+ if right.nil?
+ collector << " IS NULL"
+ else
+ collector << " = "
+ visit right, collector
+ end
+ end
+
+ def visit_Arel_Nodes_IsNotDistinctFrom(o, collector)
+ if o.right.nil?
+ collector = visit o.left, collector
+ collector << " IS NULL"
+ else
+ collector = is_distinct_from(o, collector)
+ collector << " = 0"
+ end
+ end
+
+ def visit_Arel_Nodes_IsDistinctFrom(o, collector)
+ if o.right.nil?
+ collector = visit o.left, collector
+ collector << " IS NOT NULL"
+ else
+ collector = is_distinct_from(o, collector)
+ collector << " = 1"
+ end
+ end
+
+ def visit_Arel_Nodes_NotEqual(o, collector)
+ right = o.right
+
+ collector = visit o.left, collector
+
+ if right.nil?
+ collector << " IS NOT NULL"
+ else
+ collector << " != "
+ visit right, collector
+ end
+ end
+
+ def visit_Arel_Nodes_As(o, collector)
+ collector = visit o.left, collector
+ collector << " AS "
+ visit o.right, collector
+ end
+
+ def visit_Arel_Nodes_Case(o, collector)
+ collector << "CASE "
+ if o.case
+ visit o.case, collector
+ collector << " "
+ end
+ o.conditions.each do |condition|
+ visit condition, collector
+ collector << " "
+ end
+ if o.default
+ visit o.default, collector
+ collector << " "
+ end
+ collector << "END"
+ end
+
+ def visit_Arel_Nodes_When(o, collector)
+ collector << "WHEN "
+ visit o.left, collector
+ collector << " THEN "
+ visit o.right, collector
+ end
+
+ def visit_Arel_Nodes_Else(o, collector)
+ collector << "ELSE "
+ visit o.expr, collector
+ end
+
+ def visit_Arel_Nodes_UnqualifiedColumn(o, collector)
+ collector << "#{quote_column_name o.name}"
+ collector
+ end
+
+ def visit_Arel_Attributes_Attribute(o, collector)
+ join_name = o.relation.table_alias || o.relation.name
+ collector << "#{quote_table_name join_name}.#{quote_column_name o.name}"
+ end
+ alias :visit_Arel_Attributes_Integer :visit_Arel_Attributes_Attribute
+ alias :visit_Arel_Attributes_Float :visit_Arel_Attributes_Attribute
+ alias :visit_Arel_Attributes_Decimal :visit_Arel_Attributes_Attribute
+ alias :visit_Arel_Attributes_String :visit_Arel_Attributes_Attribute
+ alias :visit_Arel_Attributes_Time :visit_Arel_Attributes_Attribute
+ alias :visit_Arel_Attributes_Boolean :visit_Arel_Attributes_Attribute
+
+ def literal(o, collector); collector << o.to_s; end
+
+ def visit_Arel_Nodes_BindParam(o, collector)
+ collector.add_bind(o.value) { "?" }
+ end
+
+ alias :visit_Arel_Nodes_SqlLiteral :literal
+ alias :visit_Integer :literal
+
+ def quoted(o, a)
+ if a && a.able_to_type_cast?
+ quote(a.type_cast_for_database(o))
+ else
+ quote(o)
+ end
+ end
+
+ def unsupported(o, collector)
+ raise UnsupportedVisitError.new(o)
+ end
+
+ alias :visit_ActiveSupport_Multibyte_Chars :unsupported
+ alias :visit_ActiveSupport_StringInquirer :unsupported
+ alias :visit_BigDecimal :unsupported
+ alias :visit_Class :unsupported
+ alias :visit_Date :unsupported
+ alias :visit_DateTime :unsupported
+ alias :visit_FalseClass :unsupported
+ alias :visit_Float :unsupported
+ alias :visit_Hash :unsupported
+ alias :visit_NilClass :unsupported
+ alias :visit_String :unsupported
+ alias :visit_Symbol :unsupported
+ alias :visit_Time :unsupported
+ alias :visit_TrueClass :unsupported
+
+ def visit_Arel_Nodes_InfixOperation(o, collector)
+ collector = visit o.left, collector
+ collector << " #{o.operator} "
+ visit o.right, collector
+ end
+
+ alias :visit_Arel_Nodes_Addition :visit_Arel_Nodes_InfixOperation
+ alias :visit_Arel_Nodes_Subtraction :visit_Arel_Nodes_InfixOperation
+ alias :visit_Arel_Nodes_Multiplication :visit_Arel_Nodes_InfixOperation
+ alias :visit_Arel_Nodes_Division :visit_Arel_Nodes_InfixOperation
+
+ def visit_Arel_Nodes_UnaryOperation(o, collector)
+ collector << " #{o.operator} "
+ visit o.expr, collector
+ end
+
+ def visit_Array(o, collector)
+ inject_join o, collector, ", "
+ end
+ alias :visit_Set :visit_Array
+
+ def quote(value)
+ return value if Arel::Nodes::SqlLiteral === value
+ @connection.quote value
+ end
+
+ def quote_table_name(name)
+ return name if Arel::Nodes::SqlLiteral === name
+ @connection.quote_table_name(name)
+ end
+
+ def quote_column_name(name)
+ return name if Arel::Nodes::SqlLiteral === name
+ @connection.quote_column_name(name)
+ end
+
+ def maybe_visit(thing, collector)
+ return collector unless thing
+ collector << " "
+ visit thing, collector
+ end
+
+ def inject_join(list, collector, join_str)
+ len = list.length - 1
+ list.each_with_index.inject(collector) { |c, (x, i)|
+ if i == len
+ visit x, c
+ else
+ visit(x, c) << join_str
+ end
+ }
+ end
+
+ def boundable?(value)
+ !value.respond_to?(:boundable?) || value.boundable?
+ end
+
+ def has_join_sources?(o)
+ o.relation.is_a?(Nodes::JoinSource) && !o.relation.right.empty?
+ end
+
+ def has_limit_or_offset_or_orders?(o)
+ o.limit || o.offset || !o.orders.empty?
+ end
+
+ # The default strategy for an UPDATE with joins is to use a subquery. This doesn't work
+ # on MySQL (even when aliasing the tables), but MySQL allows using JOIN directly in
+ # an UPDATE statement, so in the MySQL visitor we redefine this to do that.
+ def prepare_update_statement(o)
+ if o.key && (has_limit_or_offset_or_orders?(o) || has_join_sources?(o))
+ stmt = o.clone
+ stmt.limit = nil
+ stmt.offset = nil
+ stmt.orders = []
+ stmt.wheres = [Nodes::In.new(o.key, [build_subselect(o.key, o)])]
+ stmt.relation = o.relation.left if has_join_sources?(o)
+ stmt
+ else
+ o
+ end
+ end
+ alias :prepare_delete_statement :prepare_update_statement
+
+ # FIXME: we should probably have a 2-pass visitor for this
+ def build_subselect(key, o)
+ stmt = Nodes::SelectStatement.new
+ core = stmt.cores.first
+ core.froms = o.relation
+ core.wheres = o.wheres
+ core.projections = [key]
+ stmt.limit = o.limit
+ stmt.offset = o.offset
+ stmt.orders = o.orders
+ stmt
+ end
+
+ def infix_value(o, collector, value)
+ collector = visit o.left, collector
+ collector << value
+ visit o.right, collector
+ end
+
+ def infix_value_with_paren(o, collector, value, suppress_parens = false)
+ collector << "( " unless suppress_parens
+ collector = if o.left.class == o.class
+ infix_value_with_paren(o.left, collector, value, true)
+ else
+ visit o.left, collector
+ end
+ collector << value
+ collector = if o.right.class == o.class
+ infix_value_with_paren(o.right, collector, value, true)
+ else
+ visit o.right, collector
+ end
+ collector << " )" unless suppress_parens
+ collector
+ end
+
+ def aggregate(name, o, collector)
+ collector << "#{name}("
+ if o.distinct
+ collector << "DISTINCT "
+ end
+ collector = inject_join(o.expressions, collector, ", ") << ")"
+ if o.alias
+ collector << " AS "
+ visit o.alias, collector
+ else
+ collector
+ end
+ end
+
+ def is_distinct_from(o, collector)
+ collector << "CASE WHEN "
+ collector = visit o.left, collector
+ collector << " = "
+ collector = visit o.right, collector
+ collector << " OR ("
+ collector = visit o.left, collector
+ collector << " IS NULL AND "
+ collector = visit o.right, collector
+ collector << " IS NULL)"
+ collector << " THEN 0 ELSE 1 END"
+ end
+ end
+ end
+end
diff --git a/activerecord/lib/arel/visitors/visitor.rb b/activerecord/lib/arel/visitors/visitor.rb
new file mode 100644
index 0000000000..1c17184e86
--- /dev/null
+++ b/activerecord/lib/arel/visitors/visitor.rb
@@ -0,0 +1,42 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module Visitors
+ class Visitor
+ def initialize
+ @dispatch = get_dispatch_cache
+ end
+
+ def accept(object, *args)
+ visit object, *args
+ end
+
+ private
+
+ attr_reader :dispatch
+
+ def self.dispatch_cache
+ Hash.new do |hash, klass|
+ hash[klass] = "visit_#{(klass.name || '').gsub('::', '_')}"
+ end
+ end
+
+ def get_dispatch_cache
+ self.class.dispatch_cache
+ end
+
+ def visit(object, *args)
+ dispatch_method = dispatch[object.class]
+ send dispatch_method, object, *args
+ rescue NoMethodError => e
+ raise e if respond_to?(dispatch_method, true)
+ superklass = object.class.ancestors.find { |klass|
+ respond_to?(dispatch[klass], true)
+ }
+ raise(TypeError, "Cannot visit #{object.class}") unless superklass
+ dispatch[object.class] = dispatch[superklass]
+ retry
+ end
+ end
+ end
+end
diff --git a/activerecord/lib/arel/visitors/where_sql.rb b/activerecord/lib/arel/visitors/where_sql.rb
new file mode 100644
index 0000000000..c6caf5e7c9
--- /dev/null
+++ b/activerecord/lib/arel/visitors/where_sql.rb
@@ -0,0 +1,23 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module Visitors
+ class WhereSql < Arel::Visitors::ToSql
+ def initialize(inner_visitor, *args, &block)
+ @inner_visitor = inner_visitor
+ super(*args, &block)
+ end
+
+ private
+
+ def visit_Arel_Nodes_SelectCore(o, collector)
+ collector << "WHERE "
+ wheres = o.wheres.map do |where|
+ Nodes::SqlLiteral.new(@inner_visitor.accept(where, collector.class.new).value)
+ end
+
+ inject_join wheres, collector, " AND "
+ end
+ end
+ end
+end
diff --git a/activerecord/lib/arel/window_predications.rb b/activerecord/lib/arel/window_predications.rb
new file mode 100644
index 0000000000..3a8ee41f8a
--- /dev/null
+++ b/activerecord/lib/arel/window_predications.rb
@@ -0,0 +1,9 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+ module WindowPredications
+ def over(expr = nil)
+ Nodes::Over.new(self, expr)
+ end
+ end
+end