Fernando Schapachnik <fpscha@ns1.via-net-works.net.ar> writes:
> select * from aliases where alias~'^claudia.gonzalez$' \g
> alias|receptores
> -----+----------
> (0 rows)
> select * from aliases where alias~'claudia.gonzalez$' \g
> alias |receptores
> ----------------+----------
> claudia.gonzalez|claudia
> (1 row)
> Seems like there is some kind of unvisible char at the front.
I think you are getting bitten by the LIKE-index-optimization problem.
Are you running in a non-ASCII locale?
There's a good deal of traffic concerning this issue in the archives,
so I won't repeat it ...
regards, tom lane