postgresql/src
David Rowley 3798b4fe73 Relax some asserts in merge join costing code
In the planner, it was possible, given an extreme enough case containing a
large number of joins for the number of estimated rows to become infinite.
This could cause problems in initial_cost_mergejoin() where we perform
some calculations based on those row estimates.

A problem case, presented by Onder Kalaci showed an Assert failure from
an Assert checking outerstartsel <= outerendsel.  In his test case this
was effectively NaN <= Inf, which is false.  The NaN outerstartsel came
from multiplying the infinite outer_path_rows by 0.0.

In master, this problem was fixed by a90c950fc, however, that fix was too
invasive for the backbranches.  Here we just relax the Asserts to allow
them to pass.  The worst that appears to happen from this is that we show
NaN cost values and infinite row estimates in EXPLAIN.  add_path() would
have had a hard time doing anything useful with such costs, but that does
not really matter as if the row estimates were even close to accurate,
such plan would not complete this side of the heat death of the universe.

Reported-by: Onder Kalaci
Backpatch: 9.5 to 13
Discussion: https://postgr.es/m/DM6PR21MB1211FF360183BCA901B27F04D80B0@DM6PR21MB1211.namprd21.prod.outlook.com
2020-10-20 00:01:44 +13:00
..
backend Relax some asserts in merge join costing code 2020-10-20 00:01:44 +13:00
bin pg_upgrade: remove C99 compiler req. from commit 3c0471b5fd 2020-10-15 20:37:19 -04:00
common Replace use of sys_siglist[] with strsignal(). 2020-07-15 22:05:13 -04:00
include C comment: correct use of 64-"byte" cache line size 2020-09-04 13:27:52 -04:00
interfaces Teach libpq to handle arbitrary-length lines in .pgpass files. 2020-09-01 13:14:44 -04:00
makefiles Select CFLAGS_SL at configure time, not in platform-specific Makefiles. 2019-10-21 12:32:36 -04:00
pl Translation updates 2020-08-10 15:36:46 +02:00
port Stamp 9.5.23. 2020-08-10 17:23:10 -04:00
template Select CFLAGS_SL at configure time, not in platform-specific Makefiles. 2019-10-21 12:32:36 -04:00
test Fix handling of BC years in to_date/to_timestamp. 2020-09-30 15:40:23 -04:00
timezone Update time zone data files to tzdata release 2020c. 2020-10-16 21:54:14 -04:00
tools Sync our copy of the timezone library with IANA release tzcode2020c. 2020-10-16 21:40:16 -04:00
tutorial Remove no-longer-required function declarations. 2015-05-24 12:20:23 -04:00
.gitignore Convert cvsignore to gitignore, and add .gitignore for build targets. 2010-09-22 12:57:04 +02:00
bcc32.mak Autoconfiscate selection of 64-bit int type for 64-bit large object API. 2012-10-07 21:52:43 -04:00
DEVELOPERS Replace a couple of references to files that no longer exist in the source 2009-05-04 08:08:47 +00:00
Makefile Install TAP test infrastructure so it's available for extension testing. 2016-09-23 15:50:00 -04:00
Makefile.global.in Back-patch src/test/recovery and PostgresNode from 9.6 to 9.5. 2020-03-19 09:39:26 -07:00
Makefile.shlib Ensure static libraries have correct mod time even if ranlib messes it up. 2018-11-29 15:53:44 -05:00
nls-global.mk nls-global.mk: search build dir for source files, too 2016-06-07 18:55:18 -04:00
win32.mak Autoconfiscate selection of 64-bit int type for 64-bit large object API. 2012-10-07 21:52:43 -04:00