2008. 02. 1, péntek keltezéssel 03.40-kor Jochem Maas ezt írta: > Per Jessen schreef: > > Richard Lynch wrote: > > > >>> OK, what is a 'geometry column' and what is a 'spatial index' ? > >> Imagine a single column combining both longitude and latitude. > >> > >> Now imagine an index that "knows" about long/lat, and keeps > >> geographically "close" objects sorted in the index for you. > >> > >> Including "knowing" about the 180 <-> -180 degree wrap-around. > >> (Or 360 === 0 wrap-around in the other geo-system.) > >> > >> So when you ask for "theme parks near Zurich" your DB can answer in > >> milliseconds instead of minutes. > > > > Thanks Richard - I thought Nathan was talking about an abstract concept, > > not something "real". > > > > So, back the Nathans suggestion: > > > >> Back on the mysql side of things, try using geometry columns rather > >> than numerical primary keys, with spatial indexes.. it's a MASSIVE > >> performance upgrade (I've cut 5 second queries down to 0.005 by > >> using geo columns) > > > > Is this worth a try? Have others tried this? > > I for one would really like to see a concrete example of this kind of > use of geometry columns and spacial indexes as an alternative to the stand > integer based primary keys. me too greets Zoltán Németh > > > > > > > /Per Jessen, Zürich > > > -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
