+ if defined?(ActiveRecord::ConnectionAdapters::MysqlAdapter)
+ class MysqlAdapter
+ alias_method :old_native_database_types, :native_database_types
+
+ def native_database_types
+ types = old_native_database_types
+ types[:bigint] = { :name => "bigint", :limit => 20 }
+ types[:double] = { :name => "double" }
+ types[:integer_pk] = { :name => "integer DEFAULT NULL auto_increment PRIMARY KEY" }
+ types[:bigint_pk] = { :name => "bigint(20) DEFAULT NULL auto_increment PRIMARY KEY" }
+ types[:bigint_pk_64] = { :name => "bigint(64) DEFAULT NULL auto_increment PRIMARY KEY" }
+ types[:bigint_auto_64] = { :name => "bigint(64) DEFAULT NULL auto_increment" }
+ types[:bigint_auto_11] = { :name => "bigint(11) DEFAULT NULL auto_increment" }
+ types[:bigint_auto_20] = { :name => "bigint(20) DEFAULT NULL auto_increment" }
+ types[:four_byte_unsigned] = { :name=> "integer unsigned" }
+ types[:inet] = { :name=> "integer unsigned" }
+
+ enumerations.each do |e,v|
+ types[e.to_sym]= { :name => "enum('#{v.join '\',\''}')" }
+ end
+
+ types
+ end
+
+ def change_column(table_name, column_name, type, options = {})
+ unless options_include_default?(options)
+ options[:default] = select_one("SHOW COLUMNS FROM #{table_name} LIKE '#{column_name}'")["Default"]
+
+ unless type == :string or type == :text
+ options.delete(:default) if options[:default] = "";
+ end
+ end
+
+ change_column_sql = "ALTER TABLE #{table_name} CHANGE #{column_name} #{column_name} #{type_to_sql(type, options[:limit], options[:precision], options[:scale])}"
+ add_column_options!(change_column_sql, options)
+ execute(change_column_sql)
+ end
+
+ def myisam_table
+ return { :id => false, :force => true, :options => "ENGINE=MyIsam" }
+ end
+
+ def innodb_table
+ return { :id => false, :force => true, :options => "ENGINE=InnoDB" }
+ end
+
+ def innodb_option
+ return "ENGINE=InnoDB"
+ end
+
+ def change_engine (table_name, engine)
+ execute "ALTER TABLE #{table_name} ENGINE = #{engine}"
+ end
+
+ def add_fulltext_index (table_name, column)
+ execute "CREATE FULLTEXT INDEX `#{table_name}_#{column}_idx` ON `#{table_name}` (`#{column}`)"
+ end
+
+ def enumerations
+ @enumerations ||= Hash.new
+ end
+
+ def create_enumeration (enumeration_name, values)
+ enumerations[enumeration_name] = values
+ end
+
+ def drop_enumeration (enumeration_name)
+ enumerations.delete(enumeration_name)
+ end
+
+ def alter_primary_key(table_name, new_columns)
+ execute("alter table #{table_name} drop primary key, add primary key (#{new_columns.join(',')})")
+ end