How to union two tables A and B but B has one column missing while the result should have all the columns?
Question
I have A table (P1, P2, P3) and B table (P1, P2), now I want to union them together. I know I can do something like
SELECT P1, P2 FROM A UNION SELECT P1, P2 FROM B
to merge all the rows. But in the result I have to get P3 too and for rows coming from B P3 should be null, how can I do this?
1 answers
solution1
3 2019-04-21 14:27:05
(SELECT P1, P2,P3 FROM A)
UNION ALL
(SELECT P1, P2,null FROM B)
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