On Tue, 20 Apr 2004, Han Holl wrote: > Hi, > > Can anyone explain to me what I'm doing wrong: > (The first select is to show that the function rubriek exists, and does work). > I want to create an index on a computed column: > > palga=> select rubriek(rapport, lseek, 'naamvrouw',0) from main > where rapport = 'T098-20900'; > rubriek > ----------- > Ramrattan > (1 row) > palga=> create index nm_idx on main (rubriek(rapport, lseek, 'naamvrouw',0)); > ERROR: parser: parse error at or near "'naamvrouw'" at character 54 > palga=> > > This is postgresql-7.3.4-3.rhl9. In 7.3, functional indexes can only be across columns of the table, so something like the above is illegal. You can get around this my making a function that hardcodes the constants and then use that in the index and queries. In 7.4, you can index a more general set of expressions. ---------------------------(end of broadcast)--------------------------- TIP 8: explain analyze is your friend