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-rw-r--r--lib/arel/algebra/relations/operations/alias.rb7
-rw-r--r--lib/arel/algebra/relations/operations/group.rb15
-rw-r--r--lib/arel/algebra/relations/operations/join.rb41
-rw-r--r--lib/arel/algebra/relations/operations/order.rb16
-rw-r--r--lib/arel/algebra/relations/operations/project.rb19
-rw-r--r--lib/arel/algebra/relations/operations/skip.rb10
-rw-r--r--lib/arel/algebra/relations/operations/take.rb10
-rw-r--r--lib/arel/algebra/relations/operations/where.rb16
-rw-r--r--lib/arel/algebra/relations/relation.rb134
-rw-r--r--lib/arel/algebra/relations/utilities/compound.rb18
-rw-r--r--lib/arel/algebra/relations/utilities/externalization.rb24
-rw-r--r--lib/arel/algebra/relations/utilities/nil.rb7
-rw-r--r--lib/arel/algebra/relations/writes/delete.rb10
-rw-r--r--lib/arel/algebra/relations/writes/insert.rb14
-rw-r--r--lib/arel/algebra/relations/writes/update.rb14
15 files changed, 355 insertions, 0 deletions
diff --git a/lib/arel/algebra/relations/operations/alias.rb b/lib/arel/algebra/relations/operations/alias.rb
new file mode 100644
index 0000000000..67837f6a75
--- /dev/null
+++ b/lib/arel/algebra/relations/operations/alias.rb
@@ -0,0 +1,7 @@
+module Arel
+ class Alias < Compound
+ attributes :relation
+ deriving :initialize
+ alias_method :==, :equal?
+ end
+end \ No newline at end of file
diff --git a/lib/arel/algebra/relations/operations/group.rb b/lib/arel/algebra/relations/operations/group.rb
new file mode 100644
index 0000000000..04fd9fea62
--- /dev/null
+++ b/lib/arel/algebra/relations/operations/group.rb
@@ -0,0 +1,15 @@
+module Arel
+ class Group < Compound
+ attributes :relation, :groupings
+ deriving :==
+
+ def initialize(relation, *groupings, &block)
+ @relation = relation
+ @groupings = (groupings + (block_given?? [yield(relatoin)] : [])).collect { |g| g.bind(relation) }
+ end
+
+ def externalizable?
+ true
+ end
+ end
+end \ No newline at end of file
diff --git a/lib/arel/algebra/relations/operations/join.rb b/lib/arel/algebra/relations/operations/join.rb
new file mode 100644
index 0000000000..8e19254378
--- /dev/null
+++ b/lib/arel/algebra/relations/operations/join.rb
@@ -0,0 +1,41 @@
+module Arel
+ class Join < Relation
+ attributes :join_sql, :relation1, :relation2, :predicates
+ deriving :==
+ delegate :engine, :name, :to => :relation1
+ hash_on :relation1
+
+ def initialize(join_sql, relation1, relation2 = Nil.instance, *predicates)
+ @join_sql, @relation1, @relation2, @predicates = join_sql, relation1, relation2, predicates
+ end
+
+ def attributes
+ @attributes ||= (relation1.externalize.attributes +
+ relation2.externalize.attributes).collect { |a| a.bind(self) }
+ end
+
+ def wheres
+ # TESTME bind to self?
+ relation1.externalize.wheres
+ end
+
+ def ons
+ @ons ||= @predicates.collect { |p| p.bind(self) }
+ end
+
+ # TESTME
+ def externalizable?
+ relation1.externalizable? or relation2.externalizable?
+ end
+
+ def join?
+ true
+ end
+ end
+
+ class Relation
+ def join?
+ false
+ end
+ end
+end
diff --git a/lib/arel/algebra/relations/operations/order.rb b/lib/arel/algebra/relations/operations/order.rb
new file mode 100644
index 0000000000..05af3fde4d
--- /dev/null
+++ b/lib/arel/algebra/relations/operations/order.rb
@@ -0,0 +1,16 @@
+module Arel
+ class Order < Compound
+ attributes :relation, :orderings
+ deriving :==
+
+ def initialize(relation, *orderings, &block)
+ @relation = relation
+ @orderings = (orderings + (block_given?? [yield(relation)] : [])).collect { |o| o.bind(relation) }
+ end
+
+ # TESTME
+ def orders
+ (orderings + relation.orders).collect { |o| o.bind(self) }
+ end
+ end
+end \ No newline at end of file
diff --git a/lib/arel/algebra/relations/operations/project.rb b/lib/arel/algebra/relations/operations/project.rb
new file mode 100644
index 0000000000..5507ea3163
--- /dev/null
+++ b/lib/arel/algebra/relations/operations/project.rb
@@ -0,0 +1,19 @@
+module Arel
+ class Project < Compound
+ attributes :relation, :projections
+ deriving :==
+
+ def initialize(relation, *projections, &block)
+ @relation = relation
+ @projections = (projections + (block_given?? [yield(relation)] : [])).collect { |p| p.bind(relation) }
+ end
+
+ def attributes
+ @attributes ||= projections.collect { |p| p.bind(self) }
+ end
+
+ def externalizable?
+ attributes.any?(&:aggregation?) or relation.externalizable?
+ end
+ end
+end
diff --git a/lib/arel/algebra/relations/operations/skip.rb b/lib/arel/algebra/relations/operations/skip.rb
new file mode 100644
index 0000000000..930e4c94ea
--- /dev/null
+++ b/lib/arel/algebra/relations/operations/skip.rb
@@ -0,0 +1,10 @@
+module Arel
+ class Skip < Compound
+ attributes :relation, :skipped
+ deriving :initialize, :==
+
+ def externalizable?
+ true
+ end
+ end
+end \ No newline at end of file
diff --git a/lib/arel/algebra/relations/operations/take.rb b/lib/arel/algebra/relations/operations/take.rb
new file mode 100644
index 0000000000..2fd3fdf635
--- /dev/null
+++ b/lib/arel/algebra/relations/operations/take.rb
@@ -0,0 +1,10 @@
+module Arel
+ class Take < Compound
+ attributes :relation, :taken
+ deriving :initialize, :==
+
+ def externalizable?
+ true
+ end
+ end
+end \ No newline at end of file
diff --git a/lib/arel/algebra/relations/operations/where.rb b/lib/arel/algebra/relations/operations/where.rb
new file mode 100644
index 0000000000..608aaeb4b7
--- /dev/null
+++ b/lib/arel/algebra/relations/operations/where.rb
@@ -0,0 +1,16 @@
+module Arel
+ class Where < Compound
+ attributes :relation, :predicate
+ deriving :==
+
+ def initialize(relation, *predicates, &block)
+ predicate = block_given?? yield(relation) : predicates.shift
+ @relation = predicates.empty?? relation : Where.new(relation, *predicates)
+ @predicate = predicate.bind(@relation)
+ end
+
+ def wheres
+ @wheres ||= (relation.wheres + [predicate]).collect { |p| p.bind(self) }
+ end
+ end
+end
diff --git a/lib/arel/algebra/relations/relation.rb b/lib/arel/algebra/relations/relation.rb
new file mode 100644
index 0000000000..20badaf165
--- /dev/null
+++ b/lib/arel/algebra/relations/relation.rb
@@ -0,0 +1,134 @@
+module Arel
+ class Relation
+ attr_reader :count
+
+ def session
+ Session.new
+ end
+
+ def call
+ engine.read(self)
+ end
+
+ def bind(relation)
+ self
+ end
+
+ def root
+ self
+ end
+
+ module Enumerable
+ include ::Enumerable
+
+ def each(&block)
+ session.read(self).each(&block)
+ end
+
+ def first
+ session.read(self).first
+ end
+ end
+ include Enumerable
+
+ module Operable
+ def join(other_relation = nil, join_type = "INNER JOIN")
+ case other_relation
+ when String
+ Join.new(other_relation, self)
+ when Relation
+ JoinOperation.new(join_type, self, other_relation)
+ else
+ self
+ end
+ end
+
+ def outer_join(other_relation = nil)
+ join(other_relation, "LEFT OUTER JOIN")
+ end
+
+ [:where, :project, :order, :take, :skip, :group].each do |operation_name|
+ operation = <<-OPERATION
+ def #{operation_name}(*arguments, &block)
+ arguments.all?(&:blank?) && !block_given?? self : #{operation_name.to_s.classify}.new(self, *arguments, &block)
+ end
+ OPERATION
+ class_eval operation, __FILE__, __LINE__
+ end
+
+ def alias
+ Alias.new(self)
+ end
+
+ module Writable
+ def insert(record)
+ session.create Insert.new(self, record); self
+ end
+
+ def update(assignments)
+ session.update Update.new(self, assignments)
+ end
+
+ def delete
+ session.delete Deletion.new(self)
+ end
+ end
+ include Writable
+
+ JoinOperation = Struct.new(:join_sql, :relation1, :relation2) do
+ def on(*predicates)
+ Join.new(join_sql, relation1, relation2, *predicates)
+ end
+ end
+ end
+ include Operable
+
+ module AttributeAccessable
+ def [](index)
+ case index
+ when Symbol, String
+ find_attribute_matching_name(index)
+ when Attribute, Expression
+ find_attribute_matching_attribute(index)
+ when Array
+ index.collect { |i| self[i] }
+ end
+ end
+
+ def find_attribute_matching_name(name)
+ attributes.detect { |a| a.named?(name) }
+ end
+
+ def find_attribute_matching_attribute(attribute)
+ matching_attributes(attribute).max do |a1, a2|
+ (a1.original_attribute / attribute) <=> (a2.original_attribute / attribute)
+ end
+ end
+
+ private
+ def matching_attributes(attribute)
+ (@matching_attributes ||= attributes.inject({}) do |hash, a|
+ (hash[a.root] ||= []) << a
+ hash
+ end)[attribute.root] || []
+ end
+
+ def has_attribute?(attribute)
+ !matching_attributes(attribute).empty?
+ end
+ end
+ include AttributeAccessable
+
+ module DefaultOperations
+ def attributes; [] end
+ def wheres; [] end
+ def orders; [] end
+ def inserts; [] end
+ def groupings; [] end
+ def joins(formatter = nil); nil end # FIXME
+ def taken; nil end
+ def skipped; nil end
+ end
+ include DefaultOperations
+ end
+end
diff --git a/lib/arel/algebra/relations/utilities/compound.rb b/lib/arel/algebra/relations/utilities/compound.rb
new file mode 100644
index 0000000000..e33b8dbf14
--- /dev/null
+++ b/lib/arel/algebra/relations/utilities/compound.rb
@@ -0,0 +1,18 @@
+module Arel
+ class Compound < Relation
+ attr_reader :relation
+ hash_on :relation
+ delegate :joins, :join?, :inserts, :taken, :skipped, :name, :externalizable?,
+ :column_for, :engine, :table, :table_sql, :array,
+ :to => :relation
+
+ [:attributes, :wheres, :groupings, :orders].each do |operation_name|
+ operation = <<-OPERATION
+ def #{operation_name}
+ @#{operation_name} ||= relation.#{operation_name}.collect { |o| o.bind(self) }
+ end
+ OPERATION
+ class_eval operation, __FILE__, __LINE__
+ end
+ end
+end
diff --git a/lib/arel/algebra/relations/utilities/externalization.rb b/lib/arel/algebra/relations/utilities/externalization.rb
new file mode 100644
index 0000000000..bd067f2304
--- /dev/null
+++ b/lib/arel/algebra/relations/utilities/externalization.rb
@@ -0,0 +1,24 @@
+module Arel
+ class Externalization < Compound
+ attributes :relation
+ deriving :initialize, :==
+
+ def wheres
+ []
+ end
+
+ def attributes
+ @attributes ||= relation.attributes.collect(&:to_attribute).collect { |a| a.bind(self) }
+ end
+ end
+
+ class Relation
+ def externalize
+ @externalized ||= externalizable?? Externalization.new(self) : self
+ end
+
+ def externalizable?
+ false
+ end
+ end
+end
diff --git a/lib/arel/algebra/relations/utilities/nil.rb b/lib/arel/algebra/relations/utilities/nil.rb
new file mode 100644
index 0000000000..6a9d678c45
--- /dev/null
+++ b/lib/arel/algebra/relations/utilities/nil.rb
@@ -0,0 +1,7 @@
+require 'singleton'
+
+module Arel
+ class Nil < Relation
+ include Singleton
+ end
+end
diff --git a/lib/arel/algebra/relations/writes/delete.rb b/lib/arel/algebra/relations/writes/delete.rb
new file mode 100644
index 0000000000..a94067c7fa
--- /dev/null
+++ b/lib/arel/algebra/relations/writes/delete.rb
@@ -0,0 +1,10 @@
+module Arel
+ class Deletion < Compound
+ attributes :relation
+ deriving :initialize, :==
+
+ def call
+ engine.delete(self)
+ end
+ end
+end
diff --git a/lib/arel/algebra/relations/writes/insert.rb b/lib/arel/algebra/relations/writes/insert.rb
new file mode 100644
index 0000000000..6d85e9769a
--- /dev/null
+++ b/lib/arel/algebra/relations/writes/insert.rb
@@ -0,0 +1,14 @@
+module Arel
+ class Insert < Compound
+ attributes :relation, :record
+ deriving :==
+
+ def initialize(relation, record)
+ @relation, @record = relation, record.bind(relation)
+ end
+
+ def call
+ engine.create(self)
+ end
+ end
+end
diff --git a/lib/arel/algebra/relations/writes/update.rb b/lib/arel/algebra/relations/writes/update.rb
new file mode 100644
index 0000000000..e647218a80
--- /dev/null
+++ b/lib/arel/algebra/relations/writes/update.rb
@@ -0,0 +1,14 @@
+module Arel
+ class Update < Compound
+ attributes :relation, :assignments
+ deriving :==
+
+ def initialize(relation, assignments)
+ @relation, @assignments = relation, assignments
+ end
+
+ def call
+ engine.update(self)
+ end
+ end
+end
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-06 06:59:15 +0000