Re: BackgroundPsql swallowing errors on windows

> On 13 Feb 2025, at 18:39, Andres Freund <andres@anarazel.de> wrote:

> The banner being the same between queries made it hard to understand if a
> banner that appeared in the output was from the current query or a past
> query. Therefore I added a counter to it.

+    my $banner = "background_psql: QUERY_SEPARATOR $query_cnt";
+    my $banner_match = qr/(^|\n)$banner\r?\n/;
+    $self->{stdin} .= "$query\n;\n\\echo $banner\n\\warn $banner\n";
+    pump_until(
+        $self->{run}, $self->{timeout},
+        \$self->{stdout}, qr/$banner_match/);

Won't this allow "QUERY_SEPARATOR 11" to match against "QUERY_SEPARATOR 1"?
It's probably only of academic interest but appending an end-of-banner
character like "_" or something after the query counter should fix that.

> For debugging I added a "note" that shows stdout/stderr after executing the
> query, I think it may be worth keeping that, but I'm not sure.

I think it could be worth it, +1 for keeping it until it's beeb proven a
problem somewhere.

> This was a rather painful exercise.

I have no trouble believing that.

--
Daniel Gustafsson