Hi! In Thu, Oct 16, 2025 at 10:12 AM Xuneng Zhou <[email protected]> wrote: > On Wed, Oct 15, 2025 at 8:48 PM Xuneng Zhou <[email protected]> wrote: > > > > Hi, > > > > Thank you for the grammar review and the clear recommendation. > > > > On Wed, Oct 15, 2025 at 4:51 PM Álvaro Herrera <[email protected]> wrote: > > > > > > I didn't review the patch other than look at the grammar, but I disagree > > > with using opt_with in it. I think WITH should be a mandatory word, or > > > just not be there at all. The current formulation lets you do one of: > > > > > > 1. WAIT FOR LSN '123/456' WITH (opt = val); > > > 2. WAIT FOR LSN '123/456' (opt = val); > > > 3. WAIT FOR LSN '123/456'; > > > > > > and I don't see why you need two ways to specify an option list. > > > > I agree with this as unnecessary choices are confusing. > > > > > > > > So one option is to remove opt_wait_with_clause and just use > > > opt_utility_option_list, which would remove the WITH keyword from there > > > (ie. only keep 2 and 3 from the above list). But I think that's worse: > > > just look at the REPACK grammar[1], where we have to have additional > > > productions for the optional parenthesized option list. > > > > > > > > > > > > So why not do just > > > > > > +opt_wait_with_clause: > > > + WITH '(' utility_option_list ')' { $$ = $3; } > > > + | /*EMPTY*/ { $$ = NIL; } > > > + ; > > > > > > which keeps options 1 and 3 of the list above. > > > > Your suggested approach of making WITH mandatory when options are > > present looks better. > > I've implemented the change as you recommended. Please see patch 3 in v16. > > > > > > > > > > > > > > Note: you don't need to worry about WITH_LA, because that's only going > > > to show up when the user writes WITH TIME or WITH ORDINALITY (see > > > parser.c), and that's a syntax error anyway. > > > > > > > Yeah, we require '(' immediately after WITH in our grammar, the > > lookahead mechanism will keep it as regular WITH, and any attempt to > > write "WITH TIME" or "WITH ORDINALITY" would be a syntax error anyway, > > which is expected. > > > > The filename of patch 1 is incorrect due to coping. Just correct it.
Thank you for rebasing the patch. I've revised it. The significant changes has been made to 0002, where I reduced the code duplication. Also, I run pgindent and pgperltidy and made other small improvements. Please, check. ------ Regards, Alexander Korotkov Supabase
v17-0001-Add-pairingheap_initialize-for-shared-memory-usa.patch
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v17-0003-Implement-WAIT-FOR-command.patch
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v17-0002-Add-infrastructure-for-efficient-LSN-waiting.patch
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