mysql - SQL 没有返回列值为 NULL 的行

Question

如果状态值为“隐藏”，我只想排除该行。但是具有 NULL 值的行也被排除在外。主要目标是仅隐藏隐藏的状态。

这是我的查询:

SELECT t.id, t.task_name, t.status, t.assigned_user_task FROM 
`wp_hb_project_tasks` as t
INNER JOIN `wp_hb_projects` as p ON p.id = t.project_id
WHERE p.client_id = '2119' AND t.project_id = 101 AND t.status != "hidden" 
ORDER BY t.created_date DESC

第一个查询的输出是:

这是我删除“t.status != 'hidden'”的第二个查询:

SELECT t.id, t.task_name, t.status, t.assigned_user_task FROM 
`wp_hb_project_tasks` as t
INNER JOIN `wp_hb_projects` as p ON p.id = t.project_id
WHERE p.client_id = '2119' AND t.project_id = 101 ORDER BY t.created_date 
DESC

第二个查询的输出:

我也试过类似 t.status != "hidden"AND t.status IS NULL 但我仍然没有得到状态为 NULL 的行。我错过了什么吗？

Answer 1

你可以这样做:

SELECT t.id, t.task_name, t.status, t.assigned_user_task FROM 
`wp_hb_project_tasks` as t
INNER JOIN `wp_hb_projects` as p ON p.id = t.project_id
WHERE p.client_id = '2119' AND t.project_id = 101 AND (t.status != "hidden" or t.Status is null)
ORDER BY t.created_date DESC