duandong1963 2011-12-07 03:45
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如何通过一个查询使用PHP获取MySQL字段?

Basically, I have two tables (copied from WordPress): users and user_meta. User_meta has 4 columns: meta_id, user_id, meta_key, meta_value. Each row has an unique meta_id, but multiple rows can have the same user_id. I want to get everything from users (users.*) and all of the meta_values associated with the user with as few queries as possible. Also, I want to be able to use mysql_fetch_object on the returned resource.

Here's what I'm using right now:

SELECT *, (SELECT role FROM usermeta WHERE user_id=ID) as role FROM users WHERE ID=1

EDIT: I don't think I was clear that there are multiple usermeta rows with the same user_id and meta_key.

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  • doulong6761 2011-12-07 03:52
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    what about join ?

    SELECT * FROM users 
    JOIN user_meta ON users.user_id=user_meta.user_id 
    WHERE users.user_id=1
    

    Fetch Object:

    $q = mysql_query('select * from users join user_meta on users.user_id=user_meta.user_id  where users.user_id=1');
    while($r = mysql_fetch_object($q))
    {
       echo $r->user_id;
       echo ...
       echo ...
    
    }
    
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