Hello 2012/11/27 Thomas Kellerer <spam_ea...@gmx.net>: >> > So I tried: >> > >> > SELECT * >> > FROM some_table >> > WHERE regexp_matches(somecol, 'foobar') is not null; >> > >> > However that resulted in: ERROR: argument of WHERE must not return a >> set >> > >> > Hmm, even though an array is not a set I can partly see what the >> problem is >> > (although given the really cool array implementation in PostgreSQL I >> was a bit surprised). >> > >> > >> > So I though, if I convert this to an integer, it should work: >> > >> > SELECT * >> > FROM some_table >> > WHERE array_length(regexp_matches(somecol, 'foobar'), 1) > 0 >> > >> > but that still results in the same error. >> > >> > But array_length() clearly returns an integer, so why does it still >> throw this error? >> > >> > >> > I'm using 9.2.1 >> > > > >> Sounds to me like this: >> >> >> http://joecelkothesqlapprentice.blogspot.nl/2007/12/using-where-clause-parameter.html >> > > Thanks, but my question is not related to the underlying problem. > > My question is: why I cannot use regexp_matches() in the WHERE clause, even > when the result is clearly an integer value? >
use a ~ operator instead postgres=# select * from o where a ~ 'e'; a -------- pavel zdenek (2 rows) postgres=# select * from o where a ~ 'k$'; a -------- zdenek (1 row) you can use regexp_matches, but it is not effective probably postgres=# select * from o where exists (select * from regexp_matches(o.a,'ne')); a -------- zdenek (1 row) Regards Pavel Stehule > > Regards > Thomas > > > > > > -- > Sent via pgsql-sql mailing list (pgsql-sql@postgresql.org) > To make changes to your subscription: > http://www.postgresql.org/mailpref/pgsql-sql -- Sent via pgsql-sql mailing list (pgsql-sql@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-sql
