require 'bigdecimal'
require 'date'
module Arel
module Visitors
class ToSql < Arel::Visitors::Visitor
def initialize engine
@engine = engine
@connection = nil
@last_column = nil
@quoted_tables = {}
@quoted_columns = {}
@column_cache = Hash.new { |h,k| h[k] = {} }
@table_exists = {}
end
def accept object
@last_column = nil
@engine.connection_pool.with_connection do |conn|
@connection = conn
super
end
end
private
def visit_Arel_Nodes_DeleteStatement o
[
"DELETE FROM #{visit o.relation}",
("WHERE #{o.wheres.map { |x| visit x }.join ' AND '}" unless o.wheres.empty?)
].compact.join ' '
end
def visit_Arel_Nodes_UpdateStatement o
if o.orders.empty? && o.limit.nil?
wheres = o.wheres
else
stmt = Nodes::SelectStatement.new
core = stmt.cores.first
core.froms = o.relation
core.projections = [o.relation.primary_key]
stmt.limit = o.limit
stmt.orders = o.orders
wheres = [Nodes::In.new(o.relation.primary_key, [stmt])]
end
[
"UPDATE #{visit o.relation}",
("SET #{o.values.map { |value| visit value }.join ', '}" unless o.values.empty?),
("WHERE #{wheres.map { |x| visit x }.join ' AND '}" unless wheres.empty?)
].compact.join ' '
end
def visit_Arel_Nodes_InsertStatement o
[
"INSERT INTO #{visit o.relation}",
("(#{o.columns.map { |x|
quote_column_name x.name
}.join ', '})" unless o.columns.empty?),
(visit o.values if o.values),
].compact.join ' '
end
def visit_Arel_Nodes_Exists o
"EXISTS (#{visit o.select_stmt})#{
o.alias ? " AS #{visit o.alias}" : ''}"
end
def table_exists? name
return true if @table_exists.key? name
if @connection.table_exists?(name)
@table_exists[name] = true
else
false
end
end
def column_for attr
name = attr.name.to_sym
table = attr.relation.name
return nil unless table_exists? table
# If we don't have this column cached, get a list of columns and
# cache them for this table
unless @column_cache.key? table
#$stderr.puts "MISS: #{self.class.name} #{object_id} #{table.inspect} : #{name.inspect}"
columns = @connection.columns(table, "#{table}(#{name}) Columns")
@column_cache[table] = Hash[columns.map { |c| [c.name.to_sym, c] }]
end
@column_cache[table][name]
end
def visit_Arel_Nodes_Values o
"VALUES (#{o.expressions.zip(o.columns).map { |value, attr|
quote(value, attr && column_for(attr))
}.join ', '})"
end
def visit_Arel_Nodes_SelectStatement o
[
o.cores.map { |x| visit_Arel_Nodes_SelectCore x }.join,
("ORDER BY #{o.orders.map { |x| visit x }.join(', ')}" unless o.orders.empty?),
("LIMIT #{o.limit}" if o.limit),
(visit(o.offset) if o.offset),
(visit(o.lock) if o.lock),
].compact.join ' '
end
def visit_Arel_Nodes_SelectCore o
[
"SELECT #{o.projections.map { |x| visit x }.join ', '}",
("FROM #{visit o.froms}" if o.froms),
("WHERE #{o.wheres.map { |x| visit x }.join ' AND ' }" unless o.wheres.empty?),
("GROUP BY #{o.groups.map { |x| visit x }.join ', ' }" unless o.groups.empty?),
(visit(o.having) if o.having),
].compact.join ' '
end
def visit_Arel_Nodes_Having o
"HAVING #{visit o.expr}"
end
def visit_Arel_Nodes_Offset o
"OFFSET #{visit o.expr}"
end
# FIXME: this does nothing on SQLLite3, but should do things on other
# databases.
def visit_Arel_Nodes_Lock o
end
def visit_Arel_Nodes_Grouping o
"(#{visit o.expr})"
end
def visit_Arel_Nodes_Ordering o
"#{visit o.expr} #{o.descending? ? 'DESC' : 'ASC'}"
end
def visit_Arel_Nodes_Group o
visit o.expr
end
def visit_Arel_Nodes_Count o
"COUNT(#{o.distinct ? 'DISTINCT ' : ''}#{o.expressions.map { |x|
visit x
}.join(', ')})#{o.alias ? " AS #{visit o.alias}" : ''}"
end
def visit_Arel_Nodes_Sum o
"SUM(#{o.expressions.map { |x|
visit x }.join(', ')})#{o.alias ? " AS #{visit o.alias}" : ''}"
end
def visit_Arel_Nodes_Max o
"MAX(#{o.expressions.map { |x|
visit x }.join(', ')})#{o.alias ? " AS #{visit o.alias}" : ''}"
end
def visit_Arel_Nodes_Min o
"MIN(#{o.expressions.map { |x|
visit x }.join(', ')})#{o.alias ? " AS #{visit o.alias}" : ''}"
end
def visit_Arel_Nodes_Avg o
"AVG(#{o.expressions.map { |x|
visit x }.join(', ')})#{o.alias ? " AS #{visit o.alias}" : ''}"
end
def visit_Arel_Nodes_TableAlias o
"#{visit o.relation} #{quote_table_name o.name}"
end
def visit_Arel_Nodes_Between o
"#{visit o.left} BETWEEN #{visit o.right}"
end
def visit_Arel_Nodes_GreaterThanOrEqual o
"#{visit o.left} >= #{visit o.right}"
end
def visit_Arel_Nodes_GreaterThan o
"#{visit o.left} > #{visit o.right}"
end
def visit_Arel_Nodes_LessThanOrEqual o
"#{visit o.left} <= #{visit o.right}"
end
def visit_Arel_Nodes_LessThan o
"#{visit o.left} < #{visit o.right}"
end
def visit_Arel_Nodes_Matches o
"#{visit o.left} LIKE #{visit o.right}"
end
def visit_Arel_Nodes_DoesNotMatch o
"#{visit o.left} NOT LIKE #{visit o.right}"
end
def visit_Arel_Nodes_StringJoin o
"#{visit o.left} #{visit o.right}"
end
def visit_Arel_Nodes_OuterJoin o
"#{visit o.left} LEFT OUTER JOIN #{visit o.right} #{visit o.constraint}"
end
def visit_Arel_Nodes_InnerJoin o
"#{visit o.left} INNER JOIN #{visit o.right} #{visit o.constraint if o.constraint}"
end
def visit_Arel_Nodes_On o
"ON #{visit o.expr}"
end
def visit_Arel_Nodes_Not o
"NOT #{visit o.expr}"
end
def visit_Arel_Table o
if o.table_alias
"#{quote_table_name o.name} #{quote_table_name o.table_alias}"
else
quote_table_name o.name
end
end
def visit_Arel_Nodes_In o
right = o.right
"#{visit o.left} IN (#{
right.empty? ? 'NULL' : right.map { |x| visit x }.join(', ')
})"
end
def visit_Arel_Nodes_NotIn o
right = o.right
"#{visit o.left} NOT IN (#{
right.empty? ? 'NULL' : right.map { |x| visit x }.join(', ')
})"
end
def visit_Arel_Nodes_And o
"#{visit o.left} AND #{visit o.right}"
end
def visit_Arel_Nodes_Or o
"#{visit o.left} OR #{visit o.right}"
end
def visit_Arel_Nodes_Assignment o
right = quote(o.right, column_for(o.left))
"#{visit o.left} = #{right}"
end
def visit_Arel_Nodes_Equality o
right = o.right
if right.nil?
"#{visit o.left} IS NULL"
else
"#{visit o.left} = #{visit right}"
end
end
def visit_Arel_Nodes_NotEqual o
right = o.right
if right.nil?
"#{visit o.left} IS NOT NULL"
else
"#{visit o.left} != #{visit right}"
end
end
def visit_Arel_Nodes_As o
"#{visit o.left} AS #{visit o.right}"
end
def visit_Arel_Nodes_UnqualifiedColumn o
"#{quote_column_name o.name}"
end
def visit_Arel_Attributes_Attribute o
@last_column = column_for o
join_name = o.relation.table_alias || o.relation.name
"#{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 visit_Fixnum o; o end
alias :visit_Arel_Nodes_SqlLiteral :visit_Fixnum
alias :visit_Arel_SqlLiteral :visit_Fixnum # This is deprecated
alias :visit_Bignum :visit_Fixnum
def visit_String o; quote(o, @last_column) end
alias :visit_ActiveSupport_Multibyte_Chars :visit_String
alias :visit_BigDecimal :visit_String
alias :visit_Date :visit_String
alias :visit_DateTime :visit_String
alias :visit_FalseClass :visit_String
alias :visit_Float :visit_String
alias :visit_Hash :visit_String
alias :visit_Symbol :visit_String
alias :visit_Time :visit_String
alias :visit_TrueClass :visit_String
alias :visit_NilClass :visit_String
alias :visit_ActiveSupport_StringInquirer :visit_String
alias :visit_Class :visit_String
def quote value, column = nil
@connection.quote value, column
end
def quote_table_name name
@quoted_tables[name] ||= @connection.quote_table_name(name)
end
def quote_column_name name
@quoted_columns[name] ||= @connection.quote_column_name(name)
end
end
end
end