Question

我正在尝试使用以下三种类似SUM()条件执行if()操作：

第一个：

if((TIME_TO_SEC(TIMEDIFF(IF(TIME = '0000-00-00 00:00:00',sysdate() , TIME ), TIME2)) > high OR TIME IS NULL) AND TIME3 != '0000-00-00 00:00:00' AND DATE_FORMAT(TIME2, '%Y-%m-%d %H:%i') < DATE_FORMAT(now(), '%Y-%m-%d %H:%i')

第二个：

if(TIME_TO_SEC(TIMEDIFF(IF(TIME = '0000-00-00 00:00:00',sysdate() , TIME ), TIME2)) > value AND TIME3 != '0000-00-00 00:00:00' AND DATE_FORMAT(TIME2, '%Y-%m-%d %H:%i') < DATE_FORMAT(now(), '%Y-%m-%d %H:%i')

第三个：

if(TIME_TO_SEC(TIMEDIFF(IF(TIME = '0000-00-00 00:00:00',sysdate() , TIME ), TIME2)) >0 AND TIME3 != '0000-00-00 00:00:00' AND DATE_FORMAT(TIME2, '%Y-%m-%d %H:%i') < DATE_FORMAT(now(), '%Y-%m-%d %H:%i')

来自几个表的high和value两个不同的字段列。

不幸的是，我似乎无法完成这项工作，很可能是因为这句话不能SUM()组合在一起。

如何做到这一点？

编辑：添加了整个查询：

SELECT VALUE1 ,
 COUNT( * ) TOTAL 
 from ( 
  SELECT (
   if((TIME_TO_SEC(TIMEDIFF(IF(TIME = '0000-00-00 00:00:00',sysdate() , TIME ), TIME2)) > high OR TIME IS NULL) AND TIME3 != '0000-00-00 00:00:00' AND DATE_FORMAT(TIME2, '%Y-%m-%d %H:%i') < DATE_FORMAT(now(), '%Y-%m-%d %H:%i')) + 
   if(TIME_TO_SEC(TIMEDIFF(IF(TIME = '0000-00-00 00:00:00',sysdate() , TIME ), TIME2)) > value AND TIME3 != '0000-00-00 00:00:00' AND DATE_FORMAT(TIME2, '%Y-%m-%d %H:%i') < DATE_FORMAT(now(), '%Y-%m-%d %H:%i')) + 
   if(TIME_TO_SEC(TIMEDIFF(IF(TIME = '0000-00-00 00:00:00',sysdate() , TIME ), TIME2)) >0 AND TIME3 != '0000-00-00 00:00:00' AND DATE_FORMAT(TIME2, '%Y-%m-%d %H:%i') < DATE_FORMAT(now(), '%Y-%m-%d %H:%i'))) as 'ok',
if((TIME_TO_SEC(TIMEDIFF(IF(TIME = '0000-00-00 00:00:00',sysdate() , TIME ), TIME2)) > high OR TIME IS NULL) AND DATE_FORMAT(TIME2, '%Y-%m-%d %H:%i') < DATE_FORMAT(now(), '%Y-%m-%d %H:%i'),4, 
if(TIME_TO_SEC(TIMEDIFF(IF(TIME = '0000-00-00 00:00:00',sysdate() , TIME ), TIME2)) > value AND DATE_FORMAT(TIME2, '%Y-%m-%d %H:%i') < DATE_FORMAT(now(), '%Y-%m-%d %H:%i'),3, 
if(TIME_TO_SEC(TIMEDIFF(IF(TIME = '0000-00-00 00:00:00',sysdate() , TIME ), TIME2)) >0 AND DATE_FORMAT(TIME2, '%Y-%m-%d %H:%i') < DATE_FORMAT(now(), '%Y-%m-%d %H:%i'),2, 
if(TIME >'0000-00-00 00:00:00', 1,0) ))) VALUE1 
FROM table1 , table2 left outer join table3 on( value2 = value3 ) where id_param='col1' and col2 = DATE_FORMAT(if(CURTIME()>='00:00:00' and CURTIME() < '08:00:00',sysdate() - INTERVAL 1 DAY, sysdate()), '%Y-%m-%d') ) as datos GROUP BY VALUE1

这应该返回一个2columnx3rows表，其值为'ok'，'4'，'3'和'2'。

Answer 1

你可以做到

SELECT (if_cond1 + if_cond2 + if_cond3) as `x` FROM...

（根据您的上述IF扩展if_cond1，2，3。

如果您希望简化SQL扩展后的外观（非常大），可以使用sub-queries like this。

MySQL - 有条件的操作

1 个答案: