UNION question

Hi,

I have the following SQL statement (example):

SELECT tbl1.partNo || '_1' FROM myPartsTblNo1 tbl1 UNION
SELECT tbl2.partNo || '_2' FROM myPartsTblNo2 tbl2 ORDER BY partNo

Does the UNION work as it should here?
If there is the same partNo in both tables and I'm appending '_1' and '_2' there will be two different "part numbers" and the UNION doesn't fill any function. Is this correct och wrong?

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Best regards
Joacim Jarkeborn