mysql - 从表中选择排除表 2 中的值？

Question

我尝试查询从表 log 中获取数据，但不包括表 userlog 中的数据:

SELECT * FROM (`log`) LEFT JOIN `userlog` ON `userlog`.`userlogIdLog` = `log`.`LogId` 

WHERE (logTypeCategory = 0 AND LogType = 1) OR (logTypeCategory = 19 AND LogType = 1) 
OR (logTypeCategory = 0 AND LogType = 4) OR (logTypeCategory = 0 AND LogType = 8)
OR (logTypeCategory = 0 AND LogType = 12) OR (logTypeCategory = 2 AND LogType = 3)
OR (logTypeCategory = 0 AND LogType = 7) OR (logTypeCategory = 459 AND LogType = 9) 
OR (logTypeCategory = 456 AND LogType = 3) 

AND `userlogStatus` is null or userlogStatus <> 1 
AND `userlog`.`userlogIdUser` = '458' ORDER BY `LogId` DESC

但是这个查询显示了 log 中的行，尽管在表 userlog 中存在行:userlogIdLog = 1 AND userlogStatus = 1 AND userlogIdUser = 458

我在你的帮助下编辑:

select * from `log` as a 
where not exists ( select 1 from `userlog` as b where b.`userlogIdLog` = a.`LogId` AND b.`userlogIdUser` = 458 ) 

 AND (logTypeCategory = 0 AND LogType = 1)

 OR (logTypeCategory = 19 AND LogType = 1)
 OR (logTypeCategory = 0 AND LogType = 4) 
 OR (logTypeCategory = 0 AND LogType = 8) 
 OR (logTypeCategory = 0 AND LogType = 12) 
 OR (logTypeCategory = 2 AND LogType = 3) 
 OR (logTypeCategory = 0 AND LogType = 7) 
 OR (logTypeCategory = 459 AND LogType = 9) 
 OR (logTypeCategory = 456 AND LogType = 3)

但这并不正确

Answer 1

有几种方法可以从一个表中选择数据不在另一个表中的数据:

例如

select *
from `log`
where `LogId` not in 
(
    select `userlogIdLog`
    from `userlog`
)

或

select *
from `log` as a
where not exists 
(
    select 1
    from `userlog` as b
    where b.`userlogIdLog` = a.`LogId`
)

...然后在您选择上述语句之后，添加您的其余逻辑；即

AND 
(
       (logTypeCategory = 0 AND LogType = 1)
    OR (logTypeCategory = 19 AND LogType = 1)
    OR (logTypeCategory = 0 AND LogType = 4) 
    OR (logTypeCategory = 0 AND LogType = 8) 
    OR (logTypeCategory = 0 AND LogType = 12) 
    OR (logTypeCategory = 2 AND LogType = 3) 
    OR (logTypeCategory = 0 AND LogType = 7) 
    OR (logTypeCategory = 459 AND LogType = 9) 
    OR (logTypeCategory = 456 AND LogType = 3)
)