Re: logical decoding and replication of sequences

On 2/12/22 20:58, Tomas Vondra wrote:
> On 2/12/22 01:34, Tomas Vondra wrote:
>> On 2/10/22 19:17, Tomas Vondra wrote:
>>> I've polished & pushed the first part adding sequence decoding
>>> infrastructure etc. Attached are the two remaining parts.
>>>
>>> I plan to wait a day or two and then push the test_decoding part. The
>>> last part (for built-in replication) will need more work and maybe
>>> rethinking the grammar etc.
>>>
>>
>> I've pushed the second part, adding sequences to test_decoding.
>>
>> Here's the remaining part, rebased, with a small tweak in the TAP test
>> to eliminate the issue with not waiting for sequence increments. I've
>> kept the tweak in a separate patch, so that we can throw it away easily
>> if we happen to resolve the issue.
>>
>
> Hmm, cfbot was not happy about this, so here's a version fixing the
> elog() format issue reported by CirrusCI/mingw by ditching the log
> message. It was useful for debugging, but otherwise just noise.
>

There was another elog() making mingw unhappy, so here's a fix for that.

This should also fix an issue on the macOS machine. This is a thinko in
the tests, because wait_for_catchup() may not wait for all the sequence
increments after a rollback. The default mode is "write" which uses
pg_current_wal_lsn(), and that may be a bit stale after a rollback.
Doing a simple insert after the rollback fixes this (using other LSN,
like pg_current_wal_insert_lsn() would work too, but it'd cause long
waits in the test).

regards

--
Tomas Vondra
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