Re: Quirks in Sorting Pg_description

P <user2037(at)live(dot)com> writes:
> The following query works from Psql's prompt but not from Psql's "-c"
> command or from PHP's PDO interface.

> SELECT description FROM pg_catalog.pg_description WHERE description
> SIMILAR TO '\d+' ORDER BY description::integer DESC LIMIT 1;

1. I think you'll find that "SIMILAR TO '\d+'" doesn't do what you
think; or at least, if it does, that's an implementation artifact
not to be relied on. Use a POSIX regex operator instead.

2. Perhaps the context sensitivity of the behavior is explained by the
shell or PHP eating the backslash? It certainly seems like you're at
risk for different numbers of levels of backslash processing in these
cases.

regards, tom lane