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From: Peter Smith <smithpb2250@gmail.com>
Date: Thu, 8 Jul 2021 13:27:27 +1000
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Subject: Re: Column Filtering in Logical Replication
To: Rahila Syed <rahilasyed90@gmail.com>
Cc: PostgreSQL-development <pgsql-hackers@postgresql.org>
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Hi, I was wondering if/when a subset of cols is specified then does
that mean it will be possible for the table to be replicated to a
*smaller* table at the subscriber side?

e.g Can a table with 7 cols replicated to a table with 2 cols?

table tab1(a,b,c,d,e,f,g) --> CREATE PUBLICATION pub1 FOR TABLE
tab1(a,b)  --> table tab1(a,b)

~~

I thought maybe that should be possible, but the expected behaviour
for that scenario was not very clear to me from the thread/patch
comments. And the new TAP test uses the tab1 table created exactly the
same for pub/sub, so I couldn't tell from the test code either.

------
Kind Regards,
Peter Smith.
Fujitsu Australia