Re: BUG #18438: regex isnt working for "^" , ".*"

On Mon, Apr 15, 2024 at 1:20 PM PG Bug reporting form <
noreply(at)postgresql(dot)org> wrote:

> The following bug has been logged on the website:
>
> Bug reference: 18438
> Logged by: Ankur Kumar
> Email address: ankurawesome37(at)gmail(dot)com
> PostgreSQL version: 14.5
> Operating system: macos ventura version 13.5
> Description:
>
> hey , i am getting empty query result while using postgres regex operator
> "^" , ".*" etc . I am able to use "%" correctly but not getting any
> response
> for other regex operator

As the opening paragraph of the relevant docs say:

There are three separate approaches to pattern matching provided by
PostgreSQL: the traditional SQL LIKE operator, the more recent SIMILAR TO
operator (added in SQL:1999), and POSIX-style regular expressions. Aside
from the basic “does this string match this pattern?” operators, functions
are available to extract or replace matching substrings and to split a
string at matching locations.

https://www.postgresql.org/docs/current/functions-matching.html

You are mixing the first and third ones together.

David J.