Re: pg_control_recovery() return value when not in recovery

On 18 September 2017 at 05:50, Andres Freund <andres(at)anarazel(dot)de> wrote:
> Hi,
>
> Just noticed that we're returning the underlying values for
> pg_control_recovery() without any checks:
> postgres[14388][1]=# SELECT * FROM pg_control_recovery();
> ┌──────────────────────┬───────────────────────────┬──────────────────┬────────────────┬───────────────────────────────┐
> │ min_recovery_end_lsn │ min_recovery_end_timeline │ backup_start_lsn │ backup_end_lsn │ end_of_backup_record_required │
> ├──────────────────────┼───────────────────────────┼──────────────────┼────────────────┼───────────────────────────────┤
> │ 0/0 │ 0 │ 0/0 │ 0/0 │ f │
> └──────────────────────┴───────────────────────────┴──────────────────┴────────────────┴───────────────────────────────┘
> (1 row)

Yes, that would have made sense for these to be NULL

> postgres[14388][1]=# SELECT pg_is_in_recovery();
> ┌───────────────────┐
> │ pg_is_in_recovery │
> ├───────────────────┤
> │ f │
> └───────────────────┘
> (1 row)

But not this, since it is a boolean and the answer is known.

--
Simon Riggs http://www.2ndQuadrant.com/
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