select * from hbl_product where LENGTH(SUBSTR(WebSiteShopUrl,LOCATE('=',WebSiteShopUrl)+1))=4    order by WebSiteShopUrl   desc

第一种方法：

select   (@i:=@i+)   as   i,table_name.*   from   table_name,(select   @i:=)   as   it

第二种方法：

set @rownum=;

select @rownum:=@rownum+ as rownum, t.username from auth_user t limit ,;