Berkeley CSUA MOTD:Entry 21643
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2025/07/09 [General] UID:1000 Activity:popular
7/9     

2001/6/27-28 [Computer/SW/Database] UID:21643 Activity:nil
6/27    I want to do set union and set difference on some data that I have
        in mysql.  All of the items are integers, say up to 10,000,000 in
        value.  Union is easy, just select from both tables.  Difference
        is harder: mysql doesn't do "Delete from Table_X where Table_X.key
        in (Select key from Table_Y);".
        What's another good way to do it?  I'm thinking about using perl,
        with hashes for the data, and using DB_File to store the
        intermediate results.  Any other ideas?
2025/07/09 [General] UID:1000 Activity:popular
7/9     

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