Archives of the TeradataForum
Message Posted: Wed, 10 Jan 2001 @ 22:58:38 GMT
Subj: | | Re: Limited Select |
|
From: | | Jim Downey |
I attended a class at Partners this year and the instructor (whom I consider very knowledgeable within NCR) made the statement that the
EXPLAIN provides a cost and not a time estimate. They further explained (no pun intended) that it was never intended to convey an estimate
of time to run a query.
I thought that interesting since it is expressed as a unit of time.
In any case I have always used the explain as a relative measure of time for a query. Does anyone use this time estimate and expect
accurate estimates of query time? How accurate is accurate?
|