Async. functions are introduced in the 5.1.0 release, but in my opinion, there doesn't exist any supportive functions to use 'em. Let's discuss this on an example:
No, async functions have been around since PHP 3.x at lest.
3. Can somebody explain me the existence of non-standard pg_select(), pg_insert(), pg_update() and pg_delete() functions? Are there any equivalent of these functions in other PHP interfaces? Anyway, this is not the matter. What's the targeted crowd in the implementation of these functions? Are there any stuff we cannot achieve without using these functions?
They exist because PHP development is basically random and generally done by random people for random reasons.
Also, why are you mailing this here? This is a PostgreSQL PHP users list, not the PHP developers list.
4. I don't want to mention about the not described properties in the documentation. (For instance, pg_select() function's options parameter.)
They might be described on the PostgreSQL extension main page, along with all th other constants perhaps.
Chris