On Wed, Apr 19, 2023 at 8:41 PM Justin Pryzby <pry...@telsasoft.com> wrote: > > On Wed, Apr 19, 2023 at 12:20:51PM -0700, Andres Freund wrote: > > On 2023-04-19 12:16:24 -0500, Justin Pryzby wrote: > > > On Wed, Apr 19, 2023 at 11:17:04AM -0400, Melanie Plageman wrote: > > > > Ultimately this is probably fine. If we wanted to modify one of the > > > > existing tests to cover the multi-batch case, changing the select > > > > count(*) to a select * would do the trick. I imagine we wouldn't want to > > > > do this because of the excessive output this would produce. I wondered > > > > if there was a pattern in the tests for getting around this. > > > > > > You could use explain (ANALYZE). But the output is machine-dependant in > > > various ways (which is why the tests use "explain analyze so rarely). > > > > I think with sufficient options it's not machine specific. > > It *can* be machine specific depending on the node type.. > > In particular, for parallel workers, it shows "Workers Launched: ..", > which can vary even across executions on the same machine. And don't > forget about "loops=". > > Plus: > src/backend/commands/explain.c: "Buckets: %d Batches: %d Memory Usage: > %ldkB\n", > > > We have a bunch of > > EXPLAIN (ANALYZE, COSTS OFF, SUMMARY OFF, TIMING OFF) .. > > in our tests. > > There's 81 uses of "timing off", out of a total of ~1600 explains. Most > of them are in partition_prune.sql. explain analyze is barely used. > > I sent a patch to elide the machine-specific parts, which would make it > easier to use. But there was no interest.
While I don't know about other use cases, I would have used that here. Do you still have that patch laying around? I'd be interested to at least review it. - Melanie
