Hi all, I haven't found any official documentation about the postgres sql optimizer on the web, so please forgive me if there is such a document and point me to the right direction.
I've got the following problem: I cannot make the postgres SQL Optimizer use an index on a date field to filter out a date range, e.g. select * from mytable where mydate >= '2003-10-01'; Seq Scan on mytable (cost=0.00..2138.11 rows=12203 width=543) Filter: (mydate >= '2003-09-01'::date) the index is created as follows: create index query on mytable(mydate); Testing for equality gives me the index optimization: select * from mytable where mydate = '2003-10-01'; Index Scan using query on mytable (cost=0.00..54.93 rows=44 width=543) Index Cond: (mydate = '2003-09-01'::date) I have run vacuum analyze on the table. Also the table contains 25.000 records, so the index should be used in my opinion. Am I missing something ? The same seems to apply to integers. Thank you very much in advance Dimi PS The postgres version is as follows: PostgreSQL 7.3.2 on i386-redhat-linux-gnu, compiled by GCC i386-redhat-linux-gcc (GCC) 3.2.2 20030213 (Red Hat Linux 8.0 3.2.2-1) -- NEU FÜR ALLE - GMX MediaCenter - für Fotos, Musik, Dateien... Fotoalbum, File Sharing, MMS, Multimedia-Gruß, GMX FotoService Jetzt kostenlos anmelden unter http://www.gmx.net +++ GMX - die erste Adresse für Mail, Message, More! +++ ---------------------------(end of broadcast)--------------------------- TIP 7: don't forget to increase your free space map settings
