On 8/16/07, Rainer Bauer <[EMAIL PROTECTED]> wrote: > My point is that whatever search criterias are involved and how many items > are found eBay always returns the *accurate* number of items found. > > Before this drifts off: > * I do know *why* count(*) is slow using Postgres. > * I *think* that count(*) is fast on eBay because count is cheaper using > Oracle (which eBay does: <http://www.sun.com/customers/index.xml?c=ebay.xml>). > * I realize that pagination for multi-million tuple results does not make > sense.
You got me curious, so I went hunting for more hints on what eBay actually does, and found these slides from a presentation given by two eBay engineers last year: http://www.addsimplicity.com/downloads/eBaySDForum2006-11-29.pdf It's, er, a whole different ballgame there. Database behavior is barely involved in their searching; they do joins and RI across database clusters within the _application_. I knew eBay was big, but wow... ---------------------------(end of broadcast)--------------------------- TIP 4: Have you searched our list archives? http://archives.postgresql.org/
