[Rails3] Sync abstract adapter directory structure - SchemaStatements

Author: metaskills

RAILS3_NOTES

@@ -20,10 +20,45 @@ this project root. From here you can start testing, but it is best practice to u
   338 examples, 64 failures, 3 pending
 
   * Review/remove our long winded add_limit_offset!
-    With supporting add_lock! & add_limit_offset_for_association_limiting!
-
+    Supporting:
+      - add_lock!
+      - add_limit_offset_for_association_limiting!
+      - sql_for_association_limiting?
+      - change_order_direction
+  
+  * Find out if this is needed anywhere.
+    
+    def add_order_by_for_association_limiting!(sql, options)
+      # Disertation http://gist.github.com/24073
+      # Information http://weblogs.sqlteam.com/jeffs/archive/2007/12/13/select-distinct-order-by-error.aspx
+      return sql if options[:order].blank?
+      columns = sql.match(/SELECT\s+DISTINCT(.*?)FROM/)[1].strip
+      sql.sub!(/SELECT\s+DISTINCT/,'SELECT')
+      sql << "GROUP BY #{columns} ORDER BY #{order_to_min_set(options[:order])}"
+    end
+    
+    def orders_and_dirs_set(order)
+      orders = order.sub('ORDER BY','').split(',').map(&:strip).reject(&:blank?)
+      orders_dirs = orders.map do |ord|
+        dir = nil
+        ord.sub!(/\b(asc|desc)$/i) do |match|
+          if match
+            dir = match.upcase.strip
+            ''
+          end
+        end
+        [ord.strip, dir]
+      end
+    end
+    
+    def order_to_min_set(order)
+      orders_dirs = orders_and_dirs_set(order)
+      orders_dirs.map do |o,d|
+        "MIN(#{o}) #{d}".strip
+      end.join(', ')
+    end
 
 = Adapter Todo
-
+    
   * Move all sqlserver_adapter/core_ext files to sqlserver/core_ext
 

activerecord-sqlserver-adapter.gemspec

@@ -24,6 +24,7 @@ Gem::Specification.new do |s|
     "lib/active_record/connection_adapters/sqlserver_adapter/core_ext/odbc.rb",
     "lib/active_record/connection_adapters/sqlserver/database_limits.rb",
     "lib/active_record/connection_adapters/sqlserver/database_statements.rb",
+    "lib/active_record/connection_adapters/sqlserver/schema_statements.rb",
     "lib/active_record/connection_adapters/sqlserver/quoting.rb" ]
   s.test_files = [
     "test/cases/aaaa_create_tables_test_sqlserver.rb",

lib/active_record/connection_adapters/sqlserver/database_statements.rb

@@ -200,10 +200,6 @@ def zip_fields_and_rows(fields, rows)
           end
         end
 
-        def info_schema_query
-          log_info_schema_queries ? yield : ActiveRecord::Base.silence{ yield }
-        end
-
         def do_execute(sql,name=nil)
           log(sql, name || 'EXECUTE') do
             with_auto_reconnect { raw_connection_do(sql) }
@@ -294,7 +290,14 @@ def add_lock!(sql, options)
           sql.gsub! %r|LEFT OUTER JOIN\s+(.*?)\s+ON|im, "LEFT OUTER JOIN \\1 #{lock_type} ON"
           sql.gsub! %r{FROM\s([\w\[\]\.]+)}im, "FROM \\1 #{lock_type}"
         end
-
+        
+        def sql_for_association_limiting?(sql)
+          if md = sql.match(/^\s*SELECT(.*)FROM.*GROUP BY.*ORDER BY.*/im)
+            select_froms = md[1].split(',')
+            select_froms.size == 1 && !select_froms.first.include?('*')
+          end
+        end
+        
         def add_limit_offset_for_association_limiting!(sql, options)
           sql.replace %|
             SET NOCOUNT ON
@@ -310,6 +313,16 @@ def add_limit_offset_for_association_limiting!(sql, options)
           |.gsub(/[ \t\r\n]+/,' ')
         end
 
+        def change_order_direction(order)
+          order.split(",").collect {|fragment|
+            case fragment
+              when  /\bDESC\b/i     then fragment.gsub(/\bDESC\b/i, "ASC")
+              when  /\bASC\b/i      then fragment.gsub(/\bASC\b/i, "DESC")
+              else                  String.new(fragment).split(',').join(' DESC,') + ' DESC'
+            end
+          }.join(",")
+        end
+        
       end
     end
   end