mysql - Multiple Where clause with decryption -
would query decrypt usernames each condition or once , apply each condition?
select * tablea ( concat_ws( ' ', aes_decrypt(tablea.firstname, "fnkey"), aes_decrypt(tablea.lastname, "lnkey") ) '%ray%' or concat_ws( ' ', aes_decrypt(tablea.lastname, "lnkey"), aes_decrypt(tablea.firstname, "fnkey") ) '%ray%' );
i cannot tell if function evaluated once each row or more. depends on query optimizer. establish benchmark.
anyway, query inefficient. full table scan , calculate function each row. cannot use index here. not implement query on table more couple of rows.
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