[Rails3] Defensive table/column name for temporary ROW_NUMBER table.

Author: metaskills

lib/arel/engines/sql/compilers/sqlserver_compiler.rb

@@ -71,7 +71,7 @@ def select_sql_with_complex_count
         build_query \
           "SELECT COUNT([count]) AS [count_id]",
           "FROM (",
-            "SELECT #{top_clause}ROW_NUMBER() OVER (ORDER BY #{unique_orders(rowtable_order_clauses).join(', ')}) AS [rn],",
+            "SELECT #{top_clause}ROW_NUMBER() OVER (ORDER BY #{unique_orders(rowtable_order_clauses).join(', ')}) AS [__rn],",
             "1 AS [count]",
             "FROM #{relation.from_clauses}",
             (locked unless locked.blank?),
@@ -80,8 +80,8 @@ def select_sql_with_complex_count
             ("GROUP BY #{groups.join(', ')}" unless groups.blank?),
             ("HAVING #{havings.join(' AND ')}" unless havings.blank?),
             ("ORDER BY #{unique_orders(orders).join(', ')}" unless orders.blank?),
-          ") AS [_rnt]",
-          "WHERE [_rnt].[rn] > #{relation.skipped.to_i}"
+          ") AS [__rnt]",
+          "WHERE [__rnt].[__rn] > #{relation.skipped.to_i}"
       end
 
       def select_sql_without_skipped(windowed=false)
@@ -123,17 +123,17 @@ def select_sql_with_skipped
         build_query \
           "SELECT #{tc}#{rowtable_select_clauses.join(', ')}",
           "FROM (",
-            "SELECT ROW_NUMBER() OVER (ORDER BY #{unique_orders(rowtable_order_clauses).join(', ')}) AS [rn],",
+            "SELECT ROW_NUMBER() OVER (ORDER BY #{unique_orders(rowtable_order_clauses).join(', ')}) AS [__rn],",
             select_sql_without_skipped(true),
-          ") AS [_rnt]",
-          "WHERE [_rnt].[rn] > #{relation.skipped.to_i}"
+          ") AS [__rnt]",
+          "WHERE [__rnt].[__rn] > #{relation.skipped.to_i}"
       end
 
       def rowtable_select_clauses
         if single_distinct_select?
           ::Array.wrap(relation.select_clauses.first.dup.tap do |sc|
             sc.sub! 'DISTINCT', "DISTINCT #{taken_clause if relation.taken.present?}".strip
-            sc.sub! table_name_from_select_clause(sc), '_rnt'
+            sc.sub! table_name_from_select_clause(sc), '__rnt'
             sc.strip!
           end)
         elsif relation.join? && all_select_clauses_aliased?
@@ -142,7 +142,7 @@ def rowtable_select_clauses
           end
         else
           relation.select_clauses.map do |sc|
-            sc.gsub /\[#{relation.table.name}\]\./, '[_rnt].'
+            sc.gsub /\[#{relation.table.name}\]\./, '[__rnt].'
           end
         end
       end

test/cases/offset_and_limit_test_sqlserver.rb

@@ -25,28 +25,28 @@ class OffsetAndLimitTestSqlserver < ActiveRecord::TestCase
   context 'When selecting with offset' do
 
     should 'have no limit (top) if only offset is passed' do
-      assert_sql(/SELECT \[_rnt\]\.\* FROM.*WHERE \[_rnt\]\.\[rn\] > 1/) { Book.all(:offset=>1) }
+      assert_sql(/SELECT \[__rnt\]\.\* FROM.*WHERE \[__rnt\]\.\[__rn\] > 1/) { Book.all(:offset=>1) }
     end
 
   end
 
   context 'When selecting with limit and offset' do
 
     should 'only allow integers for offset' do
-      assert_sql(/WHERE \[_rnt\]\.\[rn\] > 0/) { Book.limit(10).offset('five').all }
+      assert_sql(/WHERE \[__rnt\]\.\[__rn\] > 0/) { Book.limit(10).offset('five').all }
     end
 
     should 'convert strings which look like integers to integers' do
-      assert_sql(/WHERE \[_rnt\]\.\[rn\] > 5/) { Book.limit(10).offset('5').all }
+      assert_sql(/WHERE \[__rnt\]\.\[__rn\] > 5/) { Book.limit(10).offset('5').all }
     end
 
     should 'alter SQL to limit number of records returned offset by specified amount' do
-      sql = %|SELECT TOP (3) [_rnt].* 
+      sql = %|SELECT TOP (3) [__rnt].* 
               FROM (
-                SELECT ROW_NUMBER() OVER (ORDER BY [books].[id]) AS [rn], [books].* 
+                SELECT ROW_NUMBER() OVER (ORDER BY [books].[id]) AS [__rn], [books].* 
                 FROM [books]
-              ) AS [_rnt]
-              WHERE [_rnt].[rn] > 5|.squish
+              ) AS [__rnt]
+              WHERE [__rnt].[__rn] > 5|.squish
       assert_sql(sql) { Book.limit(3).offset(5).all }
     end