Added the possibility for adapters to overwrite add_limit! to implement a...

Added the possibility for adapters to overwrite add_limit! to implement a different limiting scheme than "LIMIT X" used by MySQL, PostgreSQL, and SQLite.

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@269 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

activerecord/lib/active_record/base.rb

@@ -288,8 +288,9 @@ def find_all(conditions = nil, orderings = nil, limit = nil, joins = nil)
         sql << "#{joins} " if joins
         add_conditions!(sql, conditions)
         sql << "ORDER BY #{orderings} " unless orderings.nil?
-        sql << "LIMIT #{sanitize_conditions(limit)} " unless limit.nil?
-    
+
+        connection.add_limit!(sql, sanitize_conditions(limit)) unless limit.nil?
+
         find_by_sql(sql)
       end
   
@@ -310,7 +311,8 @@ def find_first(conditions = nil, orderings = nil)
         sql  = "SELECT * FROM #{table_name} "
         add_conditions!(sql, conditions)
         sql << "ORDER BY #{orderings} " unless orderings.nil?
-        sql << "LIMIT 1"
+
+        connection.add_limit!(sql, 1)
     
         record = connection.select_one(sql, "#{name} Load First")
         instantiate(record) unless record.nil?

activerecord/lib/active_record/connection_adapters/abstract_adapter.rb

@@ -345,6 +345,10 @@ def quote_column_name(name)
       # Returns a string of the CREATE TABLE SQL statements for recreating the entire structure of the database.
       def structure_dump() end
 
+      def add_limit!(sql, limit)
+        sql << " LIMIT #{limit}"
+      end
+
       protected
         def log(sql, name, connection, &action)
           begin

activerecord/lib/active_record/connection_adapters/sqlserver_adapter.rb

@@ -30,7 +30,6 @@ module ActiveRecord
   class Base
     def self.sqlserver_connection(config)
       require_library_or_gem 'dbi' unless self.class.const_defined?(:DBI)
-      class_eval { include ActiveRecord::SQLServerBaseExtensions }
       
       symbolize_strings_in_hash(config)
 
@@ -47,50 +46,6 @@ def self.sqlserver_connection(config)
     end
   end
 
-  module SQLServerBaseExtensions #:nodoc:
-    def self.append_features(base)
-      super
-      base.extend(ClassMethods)
-    end
-
-    module ClassMethods #:nodoc:
-      def find_first(conditions = nil, orderings = nil)
-        sql  = "SELECT TOP 1 * FROM #{table_name} "
-        add_conditions!(sql, conditions)
-        sql << "ORDER BY #{orderings} " unless orderings.nil?
-
-        record = connection.select_one(sql, "#{name} Load First")
-        instantiate(record) unless record.nil?
-      end
-
-      def find_all(conditions = nil, orderings = nil, limit = nil, joins = nil)
-        sql  = "SELECT "
-        sql << "TOP #{limit} " unless limit.nil?
-        sql << " * FROM #{table_name} " 
-        sql << "#{joins} " if joins
-        add_conditions!(sql, conditions)
-        sql << "ORDER BY #{orderings} " unless orderings.nil?
-
-        find_by_sql(sql)
-      end
-    end
-
-    def attributes_with_quotes
-      columns_hash = self.class.columns_hash
-
-      attrs = @attributes.dup
-
-      attrs = attrs.reject do |name, value|
-        columns_hash[name].identity
-      end
-
-      attrs.inject({}) do |attrs_quoted, pair|
-        attrs_quoted[pair.first] = quote(pair.last, columns_hash[pair.first])
-        attrs_quoted
-      end
-    end
-  end
-
   module ConnectionAdapters
     class ColumnWithIdentity < Column# :nodoc:
       attr_reader :identity
@@ -236,63 +191,67 @@ def create_database(name)
         execute "CREATE DATABASE #{name}"
       end
 
+      def add_limit!(sql, limit)
+        sql.gsub!(/SELECT/i, "SELECT TOP #{limit}")
+      end
+
       private
-      def select(sql, name = nil)
-        rows = []
+        def select(sql, name = nil)
+          rows = []
 
-        log(sql, name, @connection) do |conn|
-          conn.select_all(sql) do |row|
-            record = {}
+          log(sql, name, @connection) do |conn|
+            conn.select_all(sql) do |row|
+              record = {}
 
-            row.column_names.each do |col|
-              record[col] = row[col]
-            end
+              row.column_names.each do |col|
+                record[col] = row[col]
+              end
 
-            rows << record
+              rows << record
+            end
           end
+
+          rows
         end
 
-        rows
-      end
+        def enable_identity_insert(table_name, enable = true)
+          if has_identity_column(table_name)
+            "SET IDENTITY_INSERT #{table_name} #{enable ? 'ON' : 'OFF'}"
+          end
+        end
 
-      def enable_identity_insert(table_name, enable = true)
-        if has_identity_column(table_name)
-          "SET IDENTITY_INSERT #{table_name} #{enable ? 'ON' : 'OFF'}"
+        def get_table_name(sql)
+          if sql =~ /into\s*([^\s]+)\s*/i or
+              sql =~ /update\s*([^\s]+)\s*/i
+            $1
+          else
+            nil
+          end
         end
-      end
 
-      def get_table_name(sql)
-        if sql =~ /into\s*([^\s]+)\s*/i or
-            sql =~ /update\s*([^\s]+)\s*/i
-          $1
-        else
-          nil
+        def has_identity_column(table_name)
+          return get_identity_column(table_name) != nil
         end
-      end
 
-      def has_identity_column(table_name)
-        return get_identity_column(table_name) != nil
-      end
+        def get_identity_column(table_name)
+          if not @table_columns
+            @table_columns = {}
+          end
 
-      def get_identity_column(table_name)
-        if not @table_columns
-          @table_columns = {}
-        end
+          if @table_columns[table_name] == nil
+            @table_columns[table_name] = columns(table_name)
+          end
 
-        if @table_columns[table_name] == nil
-          @table_columns[table_name] = columns(table_name)
-        end
+          @table_columns[table_name].each do |col|
+            return col.name if col.identity
+          end
 
-        @table_columns[table_name].each do |col|
-          return col.name if col.identity
+          return nil
         end
 
-        return nil
-      end
-
-      def query_contains_identity_column(sql, col)
-        return sql =~ /[\(\.\,]\s*#{col}/
-      end
+        def query_contains_identity_column(sql, col)
+          return sql =~ /[\(\.\,]\s*#{col}/
+        end
     end
   end
 end
\ No newline at end of file