AND EXISTS(SELECT 1 FROM sites_locations sl WHERE items.locationID = sl.locationID AND siteID = '".LIMIT 1)
AND EXISTS(SELECT 1 FROM sites_categories sc WHERE items.categoryID = sc.categoryID AND
我正在通过一个视频教程创建一个用户注册和登录表单在php和mysql。下面的脚本应该回显login.php表单上的'exists‘,但是只显示一个空白(表示用户不存在,但实际上它是数据库中唯一的用户名) function user_exists($username) { $query = mysql_query("SELECT * FROM `users` WHERE `username` =
CREATE USER IF NOT EXISTS ...Ver 14.14 Distrib 5.7.11, for osx10.9 (x86_64) using EditLine wrapper<root:none> CREATEUSER IF NOT EXISTS 'foo'@'localhost' IDENTIFIED BY 'bar';
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我在数据库中使用NOT IN / NOT EXISTS执行DELETE或UPDATE查询时遇到问题。我有两张桌子USERS和REMARK。= '0'OrWHERE profile_id NOT EXISTS(SELECT * FROM users); DELETE FROM remark select * from