Re: Column Filtering in Logical Replication

On 3/9/22 10:20, Peter Eisentraut wrote:
>
> On 07.03.22 16:18, Tomas Vondra wrote:
>> AFAICS these issues should be resolved by the adoption of the row-filter
>> approach (i.e. it should fail the same way as for row filter).
>
> The first two patches (additional testing for row filtering feature)
> look okay to me.
>
> Attached is a fixup patch for your main feature patch (the third one).
>
> It's a bit of code and documentation cleanup, but mainly I removed the
> term "column filter" from the patch.  Half the code was using "column
> list" or similar and half the code "column filter", which was confusing.
>  Also, there seemed to be a bit of copy-and-pasting from row-filter code
> going on, with some code comments not quite sensible, so I rewrote some
> of them.  Also some code used "rf" and "cf" symbols which were a bit
> hard to tell apart.  A few more letters can increase readability.
>
> Note in publicationcmds.c OpenTableList() the wrong if condition was used.
>

Thanks, I've merged these changes into the patch.

> I'm still confused about the intended replica identity handling.  This
> patch still checks whether the column list contains the replica identity
> at DDL time.  And then it also checks at execution time.  I thought the
> latest understanding was that the DDL-time checking would be removed.  I
> think it's basically useless now, since as the test cases show, you can
> subvert those checks by altering the replica identity later.

Are you sure? Which part of the patch does that? AFAICS we only do those
checks in CheckCmdReplicaIdentity now, but maybe I'm missing something.
Are you sure you're not looking at some older patch version?

regards

--
Tomas Vondra
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