The UPDATE efficiency is too slow when c overing multiple tables

I run a SQL statement about UPDATE covering multiple tables, i feel that it is too slowly. SQL statement: update b_bb,tempdb set b_bb.zrk1=tempdb.num where b_bb.dwdm=concat(tempdb.shengbm,tempdb.shibm,tempdb.xianbm,tempdb.xiangbm,tempdb.cunbm); I modify the JOIN syntax like this: update

problem of the procedure migration from the SQLServer2000 to MySQL

SQLServer2000:Item ColorQuantity -- TableBlue 124 TableRed 223

Does MySQL 5.2 include support for Roles Based Access Control?

I find some code about role management in mysql5.2 's source code \mysql-5.2.0-falcon-alpha\storage\falcon Does MySQL 5.2 include support for roles based access control now? Does it be supported by falcon engine?