Обсуждение: multi-key index
Hi everyone, From the TODO items: Use index to restrict rows returned by multi-key index when used with non-consecutive keys to reduce heap accesses. For an index on col1,col2,col3, and a WHERE clause of col1 = 5 and col3 = 9, spin though the index checking for col1 and col3 matches, rather than just col1; also called skip-scanning. I was looking in the archives something about this but i found nothing. Where can i found the thread (i suppose should be one) about this issue? regards, Jaime Casanova _________________________________________________________ Do You Yahoo!? Información de Estados Unidos y América Latina, en Yahoo! Noticias. Visítanos en http://noticias.espanol.yahoo.com
Jaime Casanova wrote: > Hi everyone, > > >From the TODO items: > Use index to restrict rows returned by multi-key index > when used with non-consecutive keys to reduce heap > accesses. > For an index on col1,col2,col3, and a WHERE clause of > col1 = 5 and col3 = 9, spin though the index checking > for col1 and col3 matches, rather than just col1; also > called skip-scanning. > > > I was looking in the archives something about this but > i found nothing. Where can i found the thread (i > suppose should be one) about this issue? I don't remember any detailed discussion on it except that it would be a good idea. -- Bruce Momjian | http://candle.pha.pa.us pgman@candle.pha.pa.us | (610) 359-1001+ If your life is a hard drive, | 13 Roberts Road + Christ can be your backup. | Newtown Square, Pennsylvania19073
On Mon, Dec 20, 2004 at 11:58:21AM -0600, Jaime Casanova wrote: Jaime, > I was looking in the archives something about this but > i found nothing. Where can i found the thread (i > suppose should be one) about this issue? Did you use the search engine at http://www.pgsql.ru ? -- Alvaro Herrera (<alvherre[@]dcc.uchile.cl>) "Before you were born your parents weren't as boring as they are now. They got that way paying your bills, cleaning up your room and listening to you tell them how idealistic you are." -- Charles J. Sykes' advice to teenagers