mysql - number of rows in a stored procedure -

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is possible conditional select based on number of rows in stored procedure?

e.g. if select * table1 has no records, select * table2?

try this:

select col1, col2, ..., coln table1 union select col1, col2, ..., coln table2 not exists (select * table1)

this of course assumes both tables have same structure.


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