java - How to avoid null result of "SELECT max(rank) FROM test" for an empty table?

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I need to form an query in JPQL (2.0) to select a the max value (rank).

I use: SELECT max(rank) FROM test

This works fine, except the case where the table is empty, then the result is null , but I need 0 .

This would be no problem if I was able to "catch" the null with an simple if-statement, but I can't do this (the framework allows only to specify an JPA Query but no java code).

Does anybody have an idea how to tune that query to get an 0 instead of an null if the table is empty? - The database is an MySQL, and native queries or stored procedures are no option.

No native queries, no stored proc, you can't do a simple


    if (ret == null) ret = 0;

kind of thing. I'm curious, why all the restrictions? Feels like you are deliberately tying your hands behind your back. – pap Apr 19, 2012 at 9:25

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