[英]mysql-query other table condition PHP
我在mysql中有此表稱為safespot
+---------+---------------+
| term_id | userid | safe |
+---------+--------|------+
| 1 | 1 | large number, unix timestamp here
| 1 | 2 | large number, unix timestamp here
| 1 | 3 | large number, unix timestamp here
| 1 | 4 | large number, unix timestamp here
+---------+--------+
這是表users
:
+----+-------------+-------------+
| id | userid | cash |
+----+-------------+-------------+
| 1 | 1 | 100000 |
| 2 | 2 | 100000 |
| 3 | 3 | 100000 |
+----+-------------+-------------+
我該怎么做
SELECT * FROM `users` where `userid`=1 and `cash`>= 1000 and " userid do not exist in table safespot" or "if the user exists in the safestop table, check if the current timestamp is higher than the safe colum)
因此,基本上可以執行一個查詢,如果用戶ID不存在於safespot表中,或者如果確實存在,則該時間戳大於safe_value,該查詢也將返回該查詢。
SELECT * FROM `users` WHERE `userid`=1 AND `cash`>= 1000 AND (userid NOT IN (
SELECT DISTINCT userid FROM safespot
) OR (userid IN (
SELECT DISTINCT userid FROM safespot WHERE safe < UNIX_TIMESTAMP()
)
)
使用WHERE NOT EXISTS
像
SELECT u.* FROM `users` u
where u.`userid`=1
and u.`cash` >= 1000
and ( NOT EXISTS ( select 1 from safespot where userid <> u.userid)
or EXISTS (select 1 from safestop where userid = u.userid and safe < CURRENT_TIMESTAMP));
SELECT * FROM users u
LEFT JOIN safespot s ON s.userid = u.userid
WHERE
u.userid = 1
AND u.cash = 1000
AND (s.userid IS NULL OR s.safe > UNIX_TIMESTAMP())
這將使用戶返回
safespot
沒有條目,或者 safespot
與價值safe
比當前時間戳。
聲明:本站的技術帖子網頁,遵循CC BY-SA 4.0協議,如果您需要轉載,請注明本站網址或者原文地址。任何問題請咨詢:yoyou2525@163.com.