Decibel! wrote: >On Thu, Aug 16, 2007 at 12:12:03PM +0200, Rainer Bauer wrote: >> "Scott Marlowe" wrote: >> >> >When I go to amazon.com I only ever get three pages of results. ever. >> > Because they know that returning 190 pages is not that useful, as >> >hardly anyone is going to wander through that many pages. >> > >> >Google, you'll notice says "Results 1 - 10 of about 5,610,000 for >> >blacksmith" i.e. it's guesstimating as well. no reason for google to >> >look at every single row for blacksmith to know that there's about 5.6 >> >million. >> >> But if you go to eBay, they always give you an accurate count. Even if the no. >> of items found is pretty large (example: <http://search.ebay.com/new>). > >And I'd bet money that they're using a full text search of some kind to >get those results, which isn't remotely close to the same thing as a >generic SELECT count(*). Without text search (but with a category restriction): <http://collectibles.listings.ebay.com/_W0QQsacatZ1QQsocmdZListingItemList> I only wanted to show a counter-example for a big site which uses pagination to display result sets and still reports accurate counts. Anyway, what Phoenix is trying to say is that 2 queries are required: One to get the total count and one to get the tuples for the current page. I reckon it would help, if the query returning the result set could also report the total no. of tuples found. Somthing like SELECT COUNT(*), * FROM <table> WHERE <cond> OFFSET <o> LIMIT <l> Or is there a way to do that? Rainer ---------------------------(end of broadcast)--------------------------- TIP 5: don't forget to increase your free space map settings
