someone please explain this regex behaviour

Hi,

consider the following simple example, where i want to select a path by
using a where clause with the case insensitive operator "~*". Everything is
ok where i get a result of one row, but i don't understand the results with
0 rows:

backup=> select version();
version
-------------------------------------------------------------
PostgreSQL 6.5.3 on i686-pc-linux-gnu, compiled by gcc 2.95.2
(1 row)

backup=> create table foo (path varchar(300));
CREATE
backup=> insert into foo (path) values ('/My');
INSERT 29400 1
backup=> select path from foo where path ~* '/My';
path
----
/My
(1 row)

backup=> select path from foo where path ~* '^/My';
path
----
/My
(1 row)

backup=> select path from foo where path ~* '^/my';
path
----
(0 rows)

backup=> select path from foo where path ~* '/my';
path
----
/My
(1 row)

backup=> select path from foo where path ~* '/mY';
path
----
/My
(1 row)

backup=> select path from foo where path ~* '^/mY';
path
----
(0 rows)


Why e.g. does the statement "select path from foo where path ~* '^/my';"
not return the only entry "/My"? Can someone explain this?
--
Regards, martin@unix-ag.org