(minor) Outdated docs: PgBouncer now supports prepared statements

[ftambara]

In this wiki page it's noted that pgx's automatic prepared statement caching feature is incompatible with PgBouncer. It seems that with their 1.21 they added support for that.

[Jack Christensen]

Unfortunately, I don't think it changes anything for pgx. See #1784.

[ftambara]

Oh I see. Sorry, I didn't see that issue. Thanks for the info.