From dbd0140974ed768705f3680d5d6e47a56305b965 Mon Sep 17 00:00:00 2001 From: Aaron Patterson Date: Fri, 5 Nov 2010 16:33:26 -0700 Subject: arel more nicely supports EXISTS queries --- lib/arel/nodes/exists.rb | 8 ++------ lib/arel/select_manager.rb | 6 ++++++ lib/arel/tree_manager.rb | 2 +- lib/arel/visitors/to_sql.rb | 3 ++- 4 files changed, 11 insertions(+), 8 deletions(-) (limited to 'lib') diff --git a/lib/arel/nodes/exists.rb b/lib/arel/nodes/exists.rb index 167a345006..18ba8403b4 100644 --- a/lib/arel/nodes/exists.rb +++ b/lib/arel/nodes/exists.rb @@ -1,11 +1,7 @@ module Arel module Nodes - class Exists - attr_reader :select_stmt - - def initialize select_stmt - @select_stmt = select_stmt - end + class Exists < Arel::Nodes::Function + alias :select_stmt :expressions end end end diff --git a/lib/arel/select_manager.rb b/lib/arel/select_manager.rb index f2520f38d7..f6738bf26f 100644 --- a/lib/arel/select_manager.rb +++ b/lib/arel/select_manager.rb @@ -22,6 +22,12 @@ module Arel self end + ### + # Produces an Arel::Nodes::Exists node + def exists + Arel::Nodes::Exists.new @ast + end + def where_clauses #warn "where_clauses is deprecated" if $VERBOSE to_sql = Visitors::ToSql.new @engine diff --git a/lib/arel/tree_manager.rb b/lib/arel/tree_manager.rb index ca87def8d6..6176f8a250 100644 --- a/lib/arel/tree_manager.rb +++ b/lib/arel/tree_manager.rb @@ -4,7 +4,7 @@ module Arel include Arel::Relation attr_accessor :visitor - attr_reader :ast + attr_reader :ast, :engine def initialize engine @engine = engine diff --git a/lib/arel/visitors/to_sql.rb b/lib/arel/visitors/to_sql.rb index 3c96b3e259..b6af47cc57 100644 --- a/lib/arel/visitors/to_sql.rb +++ b/lib/arel/visitors/to_sql.rb @@ -62,7 +62,8 @@ module Arel end def visit_Arel_Nodes_Exists o - "EXISTS (#{visit o.select_stmt})" + "EXISTS (#{visit o.select_stmt})#{ + o.alias ? " AS #{visit o.alias}" : ''}" end def visit_Arel_Nodes_Values o -- cgit v1.2.3