MySQL 给数据排序同时追加序号列

无分组
select @rownum:=@rownum+1 as autoSeq,
sid,pid,oprimary,seq
from singlechoice,(select @rownum:=0) r
order by pid,sid

单字段分组
select (@i := case when @tableName=a.tablename then @i + 1 else 1 end ) as rowIndex,
a.*,(@tableName:=a.tablename)
from tablestyle a,(select @i:=0,@tableName:=”) as t
group by tablename,fieldname
order by tablename,(@i := case when @tableName=a.tablename then @i + 1 else 1 end )

多字段分组
select (@i := case when @tableName=concat(a.dbname,a.tablename) then @i + 1 else 1 end ) as rowIndex,
a.*,(@tableName:=concat(a.dbname,a.tablename)) as temp
from tablestyle a,(select @i:=0,@tableName:=”) as t
group by dbname,tablename,fieldname
order by dbname,tablename,(@i := case when @tableName=concat(a.dbname,a.tablename) then @i + 1 else 1 end )