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May. 24th, 2007 03:26 pmToday's SQL lesson (possibly only applicable to Oracle DB, possibly of
more general application):
One select containing a union = 10 rows, .578 ms
Second select containing a union = 10 rows, .312 ms
==========================================
Union of the above = same 10 rows, 501 SECONDS
more general application):
One select containing a union = 10 rows, .578 ms
Second select containing a union = 10 rows, .312 ms
==========================================
Union of the above = same 10 rows, 501 SECONDS
