The new versions are supposed to optimize for indexing and also for tfile conversions.
Roger
Kevin King wrote:
As I understand it, the query optimizer can shuffle things around as necessary, but the real issue is whether any of the fields are indexed. If the fields are indexed you might get better response by selecting those using an index first, and then subselecting the remaining ones after the initial select has completed. If you try to select an indexed field alongside a couple of nonindexed fields, the query optimizer may or may not choose to use the index; I'm still a bit unclear as to the line there.
-Kevin [EMAIL PROTECTED] http://www.PrecisOnline.com
-----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Aherne, John Sent: Thursday, February 24, 2005 1:52 PM To: u2-users@listserver.u2ug.org Subject: [U2] Order of criteria
Hi All,
Does the order of criteria matter in a select or list
statement, or is the execution order arbitrary?
For example, if I wanted to select vendors who sell apples in Denver,
is "Select vendors with location='Denver' and products='Apples'" the same as "Select vendors with products='Apples' and
location='Denver'" Given that out of 300 vendors, 50 sell apples, and 100 are in denver,
and 15 of those in Denver sell apples.
If it does matter, should I put the criteria that is likely to return the smallest result set first?
TIA, John
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