Php 这个SQL查询有什么问题吗？

以下是返回零行的查询，实际上不应该：

SELECT distinct(usr.user_id)
FROM
    OCN.users AS usr,
    OCN.users_groups_subscribe AS usr_grp,
    OCN.tests_users AS test_usr
WHERE
    usr.user_id=usr_grp.subscribe_user_id AND
    usr.user_id=test_usr.test_user_user_id AND
    test_user_test_id=116 AND
    (usr.user_first_name LIKE '%ajay%' OR usr.user_last_name LIKE '%ajay%')
ORDER BY usr.user_first_name, usr.user_last_name

---

唯一可能出现的问题是

test\u user\u test\u id

。我想说它可能是

test\u user.test\u user\u test\u id

基于您的另一列

test\u user.test\u user\u id

尝试：

---

首先，使用正确的ANSI连接语法：

SELECT distinct usr.user_id
FROM OCN.users AS usr
    inner join OCN.users_groups_subscribe AS usr_grp on usr_grp.subscribe_user_id = usr.user_id
    inner join OCN.tests_users AS test_usr on test_usr.test_user_user_id = usr.user_id
WHERE
    test_usr.test_user_test_id=116 AND
    (usr.user_first_name LIKE '%ajay%' OR usr.user_last_name LIKE '%ajay%')
ORDER BY usr.user_first_name, usr.user_last_name

现在试着一个接一个地注释连接（以及相应的列），看看为什么没有任何行，比如

SELECT distinct usr.user_id
FROM OCN.users AS usr
    --inner join OCN.users_groups_subscribe AS usr_grp on usr_grp.subscribe_user_id = usr.user_id
    inner join OCN.tests_users AS test_usr on test_usr.test_user_user_id = usr.user_id
WHERE
    test_usr.test_user_test_id=116 AND
    (usr.user_first_name LIKE '%ajay%' OR usr.user_last_name LIKE '%ajay%')
ORDER BY usr.user_first_name, usr.user_last_name

---

这给我带来了魔力：

SELECT distinct usr.user_id 
FROM OCN.users AS usr
    left join OCN.users_groups_subscribe AS usr_grp on usr_grp.subscribe_user_id = usr.user_id
    left join OCN.tests_users AS test_usr on test_usr.test_user_user_id = usr.user_id
WHERE
    test_usr.test_user_test_id=116 AND
    (usr.user_first_name LIKE '%pramod%' OR usr.user_last_name LIKE '%pramod%')
ORDER BY usr.user_first_name, usr.user_last_name

---

您有什么数据？查询看起来是正确的。但是没有表结构和数据。。如何测试？可能是左/右连接导致问题如果您将表结构放入SQL FIDLE中，它将非常有用-您能给出示例数据吗？

SELECT distinct usr.user_id 
FROM OCN.users AS usr
    left join OCN.users_groups_subscribe AS usr_grp on usr_grp.subscribe_user_id = usr.user_id
    left join OCN.tests_users AS test_usr on test_usr.test_user_user_id = usr.user_id
WHERE
    test_usr.test_user_test_id=116 AND
    (usr.user_first_name LIKE '%pramod%' OR usr.user_last_name LIKE '%pramod%')
ORDER BY usr.user_first_name, usr.user_last_name