From 538faf2ebc0e0e52a876f3be59c6219f620c780b Mon Sep 17 00:00:00 2001
From: Raimonds Simanovskis <raimonds.simanovskis@gmail.com>
Date: Wed, 29 Sep 2010 11:56:54 +0300
Subject: added missing require 'spec_helper' in crud_spec.rb

---
 spec/crud_spec.rb | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/spec/crud_spec.rb b/spec/crud_spec.rb
index 3485df6685..36b2a0b4e4 100644
--- a/spec/crud_spec.rb
+++ b/spec/crud_spec.rb
@@ -1,3 +1,5 @@
+require 'spec_helper'
+
 module Arel
   class FakeCrudder < SelectManager
     class FakeEngine
-- 
cgit v1.2.3


From e619462165bfab5bee85f9761df7f48a6b8f30f0 Mon Sep 17 00:00:00 2001
From: Raimonds Simanovskis <raimonds.simanovskis@gmail.com>
Date: Wed, 29 Sep 2010 13:10:17 +0300
Subject: use subquery for limit when DISTINCT is used (in Oracle)

---
 lib/arel/visitors/oracle.rb  |  6 ++++--
 spec/visitors/oracle_spec.rb | 10 ++++++++++
 2 files changed, 14 insertions(+), 2 deletions(-)

diff --git a/lib/arel/visitors/oracle.rb b/lib/arel/visitors/oracle.rb
index 659b75f16d..c691ce294e 100644
--- a/lib/arel/visitors/oracle.rb
+++ b/lib/arel/visitors/oracle.rb
@@ -6,7 +6,9 @@ module Arel
       def visit_Arel_Nodes_SelectStatement o
         o = order_hacks(o)
 
-        if o.limit && o.orders.empty? && !o.offset
+        # 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.offset && o.cores.first.projections.first !~ /^DISTINCT /
           o.cores.last.wheres.push Nodes::LessThanOrEqual.new(
             Nodes::SqlLiteral.new('ROWNUM'), o.limit
           )
@@ -31,7 +33,7 @@ module Arel
           eosql
         end
 
-        if o.limit && !o.orders.empty?
+        if o.limit
           o       = o.dup
           limit   = o.limit
           o.limit = nil
diff --git a/spec/visitors/oracle_spec.rb b/spec/visitors/oracle_spec.rb
index cdf0e3427f..93ade3ef3c 100644
--- a/spec/visitors/oracle_spec.rb
+++ b/spec/visitors/oracle_spec.rb
@@ -71,6 +71,16 @@ module Arel
             }
           end
 
+          it 'creates a subquery when there is DISTINCT' do
+            stmt = Nodes::SelectStatement.new
+            stmt.cores.first.projections << Nodes::SqlLiteral.new('DISTINCT id')
+            stmt.limit = 10
+            sql = @visitor.accept stmt
+            sql.should be_like %{
+              SELECT * FROM (SELECT DISTINCT id) WHERE ROWNUM <= 10
+            }
+          end
+
           it 'creates a different subquery when there is an offset' do
             stmt = Nodes::SelectStatement.new
             stmt.limit = 10
-- 
cgit v1.2.3