You're right.

Of course one could union several queries together, like so (assuming the same table t): 

          ( select * from t where coln1='?' )
union all ( select * from t where coln2='?' )
union all ( select * from t where coln3='?' )
-- ... (etcetera)

[download]

This way there is only one database/network trip. Of course, it can easily make the call side (application) more complicated and I wouldn't recommend it. But it's not so long ago that that performance gain could be irresistable.

In reply to Re^2: PERL DBI MODULE by erix
in thread PERL DBI MODULE by PiyaPerl

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