Fix last insert ID not being returned with postgresql.

[laacz]

When using PostgreSQL, upon saving new entries id is not being updated.

That's because PDO's implementation of lastInsertId requires sequence name as a parameter. One of three available options is fetching LASTVAL(). All three are described in the answer to this SO question.

I 'fixed' it by adding driver specific last_insert_id() method to ORM class.

[treffynnon]

I am thinking that RETURNING id is possibly the better of all the options there for this. I don't regularly use Postgres though so can anyone else chime in?

[treffynnon]

This feature is going to slip to version 1.4 as there has been no further input.

[laacz]

Thank you. I missed this notification from github. Answering your question - RETURNING would be an option, but this feature is present only since Postgres 9.1.

[treffynnon]

Is it likely that the servers will not have been upgraded to version 9.1? Ubuntu appear to have been running 9.1 as the default postgresql package for over a year now (Oneiric) although Debian are still 8.4 from what I can see.

[laacz]

I would bet that there is still a lot of 8.x servers out there. Some are just legacy systems, others probably do not upgrade for various reasons (plugin compatibility, syntax changes, no need to, etc). I would not rely on 9.1 being the minimum version available.

[treffynnon]

According to comments in the answer on the SO question that you linked to the RETURNING method works in 8.2.

In fact as I go back through documentation RETURNING appears to exists right back to version 8.2 of PostgreSQL.

[laacz]

@treffynnon Oh, then I read it diagonally. Relied on best answer. Then, of course, RETURNING is the way to go and falling back to SELECT from sequence only on older versions.

[treffynnon]

Is there anyway you could have a go at getting RETURNING to work as a pull request instead of LASTVAL()?

[laacz]

OK, I'll do that. That will be separate pull request then.

[treffynnon]

That would be perfect. Thanks!