Sebastian Siewior schrob: > Hello hopefully correct List,
perfectly. > I was trying to do something that is not working as it supposed to. > First I created a table: > > create table t ( > col CHAR (3) CONSTRAINT numonly_col CHECK ( col ~ '^\\d+$' ) > ); > > This check avoids non-numbers like '1a1' and allows '123'. For some > reason, I'm unable to find out why, it also avoids things like '1' and > '12'. Could someone please give me hint? :) Char is padded with spaces, and that is also why your regexp is not matching in these situations. You could either adjust your regexp to match the trailing spaces or use varchar(3) instead: --8<---------------cut here---------------start------------->8--- scratch=# select '1'::char(3) ~ '^\\d+$'; ?column? ---------- f (1 row) scratch=# select '1'::char(3) ~ '^\\d+\\s*$'; ?column? ---------- t (1 row) scratch=# select '1'::varchar(3) ~ '^\\d+$'; ?column? ---------- t (1 row) --8<---------------cut here---------------end--------------->8--- regards Andreas -- ---------------------------(end of broadcast)--------------------------- TIP 6: explain analyze is your friend
