PG Bug reporting form <noreply(at)postgresql(dot)org> writes:
> https://www.postgresql.org/docs/11/indexes-types.html, according to this
> page, btree index is supposed to work for where clause col like 'foo%', but
> does not work for me. we are on aurora postgres 11, I also tested on
> postgres 11, it does not work either.
As the manual explains, that will not work by default unless your
database locale is C (which is an uncommon default nowadays).
It's also possible that Aurora has changed something that keeps
it from working, but I'd investigate the locale angle first.
regards, tom lane