2008/2/26, Tom Lane <tgl@xxxxxxxxxxxxx>: > "Laurent Raufaste" <analogue@xxxxxxxx> writes: > > > 2008/2/26, Tom Lane <tgl@xxxxxxxxxxxxx>: > > >> If it's 8.2 or later then increasing the stats target for _comment.path > >> to 100 or more would likely help. > > > I'm using PG 8.2.4. > > We are using 100 as default_statistics_target by default and all our > > column are using this value: > > > Hmm, that ought to be enough to activate the better selectivity > estimator. > > Unless ... did you update this database from a pre-8.2 DB that already > had contrib/ltree in it? If so, did you just load the existing old > definition of ltree as part of your dump, or did you install 8.2's > version fresh? I'm wondering if you have a definition of operator <@ > that doesn't specify the new selectivity estimator. Please try a > pg_dump -s and see what it shows as the definition of <@. > > regards, tom lane > Here's the first definition of the <@ operator in my dump: -- -- Name: <@; Type: OPERATOR; Schema: public; Owner: postgres -- CREATE OPERATOR <@ ( PROCEDURE = ltree_risparent, LEFTARG = ltree, RIGHTARG = ltree, COMMUTATOR = @>, RESTRICT = ltreeparentsel, JOIN = contjoinsel ); ALTER OPERATOR public.<@ (ltree, ltree) OWNER TO postgres; Our data was created on an older PG (8.1.x) but we installed 8.2.x from scratch, only dumping the schema and the data in it. I used ltree found in the 8.2.4 source. Do you think an update of ltree, or better of the database will fix the problem ? We plan on upgrading to the 8.3 branch in the next weeks, but this behavior can't wait this much as our servers are overburned from time to time =( Thanks for your help ;) -- Laurent Raufaste <http://www.glop.org/> ---------------------------(end of broadcast)--------------------------- TIP 4: Have you searched our list archives? http://archives.postgresql.org