duanji9311 2009-02-07 08:07
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在MySQL中检索多列PK

How do I retrieve a multi-column PK in MySQL?

For example I have my primary key setup as PRIMARY KEY (donor_id,country_id)

Now if I want to get the primary key value without concatenating those 2 fields in a select query, how do I do that? I want to use this in a view (or better yet, directly in phpmaker).

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  • dongyi2534 2009-02-07 08:14
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    It's not clear what you mean by "without concatenating". A simple

    SELECT donor_id, country_id FROM table WHERE ...;
    

    will retrieve the records; you don't need to apply a CONCATENATE() function or anything like that. This is the Right Way to select two records from a table; the fact that they both happen to be declared part of the primary key changes nothing.

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