MySQL 'user_id' in where 子句是不明确的问题
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MySQL 'user_id' in where clause is ambiguous problem
提问by HoMe
How can I correct the problem I keep getting from the code below which states 'user_id' in where clause is ambiguous. Thanks for the help in advance.
我怎样才能纠正我从下面的代码中得到的问题'user_id' in where clause is ambiguous。我在这里先向您的帮助表示感谢。
Here is the mysql table.
这是mysql表。
SELECT user.*, user_info.*
FROM user
INNER JOIN user_info ON user.user_id = user_info.user_id
WHERE user_id='$user_id'
回答by Daniel Vassallo
You simply need to specify which user_idto use, since both the user_infoand usertable have a field called user_id:
您只需要指定user_id要使用的对象，因为 theuser_info和usertable 都有一个名为 的字段user_id：
... WHERE user.user_id='$user_id'
SQL wouldn't tolerate this ambiguity, since for what it knows, both fields can represent totally different data.
SQL 不会容忍这种歧义，因为就它所知，这两个字段可以表示完全不同的数据。
回答by Dave Markle
The solution is to select each column explicitly everywhere. Don't use user.* and user_info.* in your select list, either:
解决方案是在任何地方明确选择每一列。不要在选择列表中使用 user.* 和 user_info.*，或者：
SELECT u.user_id, u.user_fudge, ui.foo, ui.bar
FROM user u
INNER JOIN user_info ui
ON ui.user_id = u.user_id
WHERE u.user_id = '$user_id';
回答by user3773680
You should be mention alias name of your column and assign to user_id like
你应该提到你的列的别名并分配给 user_id 就像
SELECT user.*, user_info.*
FROM user as u
INNER JOIN user_info as ui ON u.user_id = ui.user_id
WHERE u.user_id='$user_id'
回答by Dee_wab
Try this.
尝试这个。
SELECT u.user_id, u.user_fudge, ui.foo, ui.bar
FROM user AS u
INNER JOIN user_info AS ui
ON ui.user_id = u.user_id
WHERE u.user_id = '$user_id';
