Re: BUG #19681: ILIKE rejected on nondeterministic collations while LIKE works

On Thu, Sep 10, 2026 at 5:38 PM PG Bug reporting form
<noreply(at)postgresql(dot)org> wrote:
>
> The following bug has been logged on the website:
>
>
> The documentation (func-matching.sgml) states that LIKE supports
> nondeterministic collations and that SIMILAR TO / POSIX regex do not — but
> says nothing about ILIKE. Meanwhile ILIKE's documented definition is exactly

I see that this doc
https://www.postgresql.org/docs/18/functions-matching.html#FUNCTIONS-LIKE
says that ILIKE doesn't support non-deterministic-collations.

"The key word ILIKE can be used instead of LIKE to make the match
case-insensitive according to the active locale. (But this does not
support nondeterministic collations.)"

So this looks like it is working as intended.

Thanks
Nitin Motiani
Senior Software Engineer,
Google