On Thu, Jan 21, 2021 at 1:30 PM Kyotaro Horiguchi <horikyota....@gmail.com> wrote:
> Hello. > > At Wed, 18 Nov 2020 15:05:00 +0300, a.pervush...@postgrespro.ru wrote in > > I've changed the BEGIN WAIT FOR LSN statement to core functions > > pg_waitlsn, pg_waitlsn_infinite and pg_waitlsn_no_wait. > > Currently the functions work inside repeatable read transactions, but > > waitlsn creates a snapshot if called first in a transaction block, > > which can possibly lead the transaction to working incorrectly, so the > > function gives a warning. > > According to the discuttion here, implementing as functions is not > optimal. As a Poc, I made it as a procedure. However I'm not sure it > is the correct implement as a native procedure but it seems working as > expected. > > > Usage examples > > ========== > > select pg_waitlsn(‘LSN’, timeout); > > select pg_waitlsn_infinite(‘LSN’); > > select pg_waitlsn_no_wait(‘LSN’); > > The first and second usage is coverd by a single procedure. The last > function is equivalent to pg_last_wal_replay_lsn(). As the result, the > following procedure is provided in the attached. > > pg_waitlsn(wait_lsn pg_lsn, timeout integer DEFAULT -1) > > Any opinions mainly compared to implementation as a command? > > regards. > > -- > Kyotaro Horiguchi > NTT Open Source Software Center > The patch (pg_waitlsn_v10_2_kh.patch) does not compile successfully and has compilation errors. Can you please take a look? https://cirrus-ci.com/task/6241565996744704 xlog.c:45:10: fatal error: commands/wait.h: No such file or directory #include "commands/wait.h" ^~~~~~~~~~~~~~~~~ compilation terminated. make[4]: *** [<builtin>: xlog.o] Error 1 make[4]: *** Waiting for unfinished jobs.... make[3]: *** [../../../src/backend/common.mk:39: transam-recursive] Error 2 make[2]: *** [common.mk:39: access-recursive] Error 2 make[1]: *** [Makefile:42: all-backend-recurse] Error 2 make: *** [GNUmakefile:11: all-src-recurse] Error 2 I am changing the status to "Waiting on Author" -- Ibrar Ahmed
