The following bug has been logged online:
Bug reference: 4574
Logged by: Nat!
Email address: nat@mulle-kybernetik.com
PostgreSQL version: 8.3.5
Operating system: Mac OS X 10.4
Description: LIKE fails on non-varying character with no wildcards
Details:
The documentation claims:
http://www.postgresql.org/docs/8.3/interactive/functions-matching.html#FUNCT
IONS-LIKE
"If pattern does not contain percent signs or underscore, then the pattern
only represents the string itself; in that case LIKE acts like the equals
operator."
But:
create temporary table foo ( nummer character(12) );
insert into foo ( nummer) values( '1848' ) ;
select count(*) from foo where nummer = '1848' ;
-- returns 1
select count(*) from foo where nummer like '1848' ;
-- returns 0
drop table foo;
Whereas:
create temporary table bar ( nummer character varying );
insert into bar ( nummer) values( '1848' ) ;
select count(*) from bar where nummer = '1848' ;
-- returns 1
select count(*) from bar where nummer like '1848' ;
-- returns 1
drop table bar;
OTOH. Oracle has the same behaviour.