通過虛擬表獲取結果集的行的標識號,或者想知道數據庫某一條數據的排名,或者獲取時間的多少天前記錄等。
SQL如下:
SELECT @rowno:=@rowno+1 AS rowno,a.* FROM `tbl_crm_card_info` a,(SELECT @rowno:=0 )t LIMIT 0,10
SQL2:
SELECT @rowno:=@rowno +1 AS lineno ,DATE_SUB(CURDATE(),INTERVAL @rowno DAY) AS statdate,b.* FROM (SELECT @rowno:=0) a ,
tbl_crm_card_info b LIMIT 31