Re: GetSubscriptionRelations declares too many scan keys

On Mon, May 10, 2021 at 2:46 PM Julien Rouhaud <rjuju123(at)gmail(dot)com> wrote:
>
> On Mon, May 10, 2021 at 07:09:29PM +1000, Peter Smith wrote:
> > On Mon, May 10, 2021 at 6:09 PM Bharath Rupireddy
> > <bharath(dot)rupireddyforpostgres(at)gmail(dot)com> wrote:
> > >
> > > On Mon, May 10, 2021 at 12:36 PM Peter Smith <smithpb2250(at)gmail(dot)com> wrote:
> > > >
> > > > The function GetSubscriptionRelations was declaring ScanKeyData
> > > > skey[2]; but actually
> > > > only uses 1 scan key. It seems like the code was cut/paste from other
> > > > nearby functions
> > > > which really are using 2 keys.
> > > >
> > > > PSA a trivial patch to declare the correct number of keys for this function.
> > >
> > > +1 for the change. It looks like a cut/paste type introduced by the
> > > commit 7c4f52409a.
> > >
> > > A comment on the patch: why do we need to declare an array of 1
> > > element ScanKeyData skey[1];? Instead, can we just do ScanKeyData
> > > skey;?
> >
> > IMO declaring skey[1] is better because then the code can share the
> > same pattern as every other ScanData skey[n] code.
> >
> > Please search PG source code for "ScanData skey[1];" - there are
> > dozens of precedents where other people felt the same as me for
> > declaring single keys.
>
> AFAICT there are 73 occurences vs 62 of the "Scandata skey;". I don't think
> there's a huge consensus for one over the other.

I think both Scandata skey[1]; and Scandata skey; are used. But IMHO
using Scandata skey; looks better.

--
Regards,
Dilip Kumar
EnterpriseDB: http://www.enterprisedb.com