Re: Optionally automatically disable logical replication subscriptions on error

> On Jun 21, 2021, at 5:57 PM, Peter Smith <smithpb2250(at)gmail(dot)com> wrote:
>
> * Is the goal mainly to help automated (TAP) testing?

Absolutely, that was my original motivation. But I don't think that is the primary reason the patch would be accepted. There is a cost to having the logical replication workers attempt ad infinitum to apply a transaction that will never apply.

Also, if you are waiting for a subscription to catch up, it is far from obvious that you will wait forever.

> In that case,
> then maybe you do want to store the error message somewhere other than
> the log files. But still I wonder if results would be unpredictable
> anyway - e.g if there are multiple tables all with errors then it
> depends on the tablesync order of execution which error you see caused
> the auto-disable, right? And if it is not predictable maybe it is less
> useful.

But if you are writing a TAP test, you should be the one controlling whether that is the case. I don't think it would be unpredictable from the point of view of the test author.

—
Mark Dilger
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