Commit Graph

45705 Commits

Author SHA1 Message Date
Thomas Munro 18e586741b Fix typos.
Author: David Rowley
Discussion: https://postgr.es/m/CAKJS1f8du35u5DprpykWvgNEScxapbWYJdHq%2Bz06Wj3Y2KFPbw%40mail.gmail.com
2018-08-27 09:32:59 +12:00
Tom Lane bff84a547d Make syslogger more robust against failures in opening CSV log files.
The previous coding figured it'd be good enough to postpone opening
the first CSV log file until we got a message we needed to write there.
This is unsafe, though, because if the open fails we end up in infinite
recursion trying to report the failure.  Instead make the CSV log file
management code look as nearly as possible like the longstanding logic
for the stderr log file.  In particular, open it immediately at postmaster
startup (if enabled), or when we get a SIGHUP in which we find that
log_destination has been changed to enable CSV logging.

It seems OK to fail if a postmaster-start-time open attempt fails, as
we've long done for the stderr log file.  But we can't die if we fail
to open a CSV log file during SIGHUP, so we're still left with a problem.
In that case, write any output meant for the CSV log file to the stderr
log file.  (This will also cover race-condition cases in which backends
send CSV log data before or after we have the CSV log file open.)

This patch also fixes an ancient oversight that, if CSV logging was
turned off during a SIGHUP, we never actually closed the last CSV
log file.

In passing, remember to reset whereToSendOutput = DestNone during syslogger
start, since (unlike all other postmaster children) it's forked before the
postmaster has done that.  This made for a platform-dependent difference
in error reporting behavior between the syslogger and other children:
except on Windows, it'd report problems to the original postmaster stderr
as well as the normal error log file(s).  It's barely possible that that
was intentional at some point; but it doesn't seem likely to be desirable
in production, and the platform dependency definitely isn't desirable.

Per report from Alexander Kukushkin.  It's been like this for a long time,
so back-patch to all supported branches.

Discussion: https://postgr.es/m/CAFh8B==iLUD_gqC-dAENS0V+kVrCeGiKujtKqSQ7++S-caaChw@mail.gmail.com
2018-08-26 14:21:55 -04:00
Jeff Davis ba9d35b8eb Reconsider new file extension in commit 91f26d5f.
Andres and Tom objected to the choice of the ".tmp"
extension. Changing to Andres's suggestion of ".spill".

Discussion: https://postgr.es/m/88092095-3348-49D8-8746-EB574B1D30EA%40anarazel.de
2018-08-25 22:52:46 -07:00
Bruce Momjian cc2e457fe8 doc: "Latest checkpoint location" will not match in pg_upgrade
Mention that "Latest checkpoint location" will not match in pg_upgrade
if the standby server is still running during the upgrade, which is
possible.  "Match" text first appeared in PG 9.5.

Reported-by: Paul Bonaud

Discussion: https://postgr.es/m/c7268794-edb4-1772-3bfd-04c54585c24e@trainline.com

Backpatch-through: 9.5
2018-08-25 13:35:14 -04:00
Bruce Momjian dcb2efdbdd doc: add doc link for 'applicable_roles'
Reported-by: Ashutosh Sharma

Discussion: https://postgr.es/m/CAE9k0PnhnL6MNDLuvkk8USzOa_DpzDzFQPAM_uaGuXbh9HMKYw@mail.gmail.com

Author: Ashutosh Sharma

Backpatch-through: 9.3
2018-08-25 13:01:24 -04:00
Jeff Davis 91f26d5fe4 Change extension of spilled ReorderBufferChange data to ".tmp".
The previous extension, ".snap", was chosen for historical reasons and
became confusing.

Discussion: https://postgr.es/m/CAMp0ubd_P8vBGx8=MfDXQJZxHA5D_Zarw5cCkDxJ_63+pWRJ9w@mail.gmail.com
2018-08-25 09:36:09 -07:00
Jeff Davis e75733d46c Comment fix for rewriteheap.h.
The description of the filename for mapping files did not match the
code.
2018-08-25 09:17:14 -07:00
Bruce Momjian 7abf8ee1e8 docs: Clarify pg_ctl initdb option text to match options proto.
The options string appeared in PG 10.

Reported-by: pgsql-kr@postgresql.kr

Discussion: https://postgr.es/m/153500377658.1378.6587007319641704057@wrigleys.postgresql.org

Backpatch-through: 10
2018-08-25 12:01:53 -04:00
Bruce Momjian a6ca9c2a1b docs: clarify plpython SD and GD dictionary behavior
Reported-by: Adam Bielański

Discussion: https://postgr.es/m/153484305538.1370.7605856225879294548@wrigleys.postgresql.org

Backpatch-through: 9.3
2018-08-25 11:52:30 -04:00
Andres Freund 8ecdefc261 Remove test for VA_ARGS, implied by C99.
This simplifies logic / reduces duplication in a few headers.

Author: Andres Freund
Discussion: https://postgr.es/m/97d4b165-192d-3605-749c-f614a0c4e783@2ndquadrant.com
2018-08-24 10:41:45 -07:00
Andres Freund cb92520563 LLVMJIT: LLVMGetHostCPUFeatures now is upstream, use LLMV version if available.
Noticed thanks to buildfarm animal seawasp.

Author: Andres Freund
Backpatch: v11-, where LLVM based JIT compliation was introduced.
2018-08-24 10:21:38 -07:00
Tom Lane b0c5da615e Suppress uninitialized-variable warning in new SCRAM code.
While we generally don't sweat too much about "may be used uninitialized"
warnings from older compilers, I noticed that there's a fair number of
buildfarm animals that are producing such a warning *only* for this
variable.  So it seems worth silencing.
2018-08-24 10:51:10 -04:00
Michael Paquier db72302b0a Fix documentation for run-time partition pruning
Since 5220bb7, not only Append, but also MergeAppend support the
operation.

Author: Amit Langote
Discussion: https://postgr.es/m/59d8eb92-4536-c44e-54e2-305b9b3d8eb7@lab.ntt.co.jp
2018-08-24 22:54:07 +09:00
Andres Freund 143290efd0 Introduce minimal C99 usage to verify compiler support.
This just converts a few for loops in postgres.c to declare variables
in the loop initializer, and uses designated initializers in smgr.c's
definition of smgr callbacks.

Author: Andres Freund
Discussion: https://postgr.es/m/97d4b165-192d-3605-749c-f614a0c4e783@2ndquadrant.com
2018-08-23 18:36:07 -07:00
Andres Freund d9dd406fe2 Require C99 (and thus MSCV 2013 upwards).
In 86d78ef50e I enabled configure to check for C99 support, with the
goal of checking which platforms support C99.  While there are a few
machines without C99 support among our buildfarm animals,
de-supporting them for v12 was deemed acceptable.

While not tested in aforementioned commit, the biggest increase in
minimum compiler version comes from MSVC, which gained C99 support
fairly late. The subset in MSVC 2013 is sufficient for our needs, at
this point. While that is a significant increase in minimum version,
the existing windows binaries are already built with a new enough
version.

Make configure error out if C99 support could not be detected. For
MSVC builds, increase the minimum version to 2013.

The increase to MSVC 2013 allows us to get rid of VCBuildProject.pm,
as that was only required for MSVC 2005/2008.

Author: Andres Freund
Discussion: https://postgr.es/m/97d4b165-192d-3605-749c-f614a0c4e783@2ndquadrant.com
2018-08-23 18:33:57 -07:00
Michael Paquier a569eea699 Add more tests for VACUUM skips with partitioned tables
A VACUUM or ANALYZE command listing directly a partitioned table expands
it to its partitions, causing all elements of a tree to be processed
with individual ownership checks done.  This results in different
relation skips depending on the ownership policy of a tree, which may
not be consistent for a partition tree.  This commit adds more tests to
ensure that any future refactoring allows to keep a consistent behavior,
or at least that any changes done are easily identified and checked.
The current behavior of VACUUM with partitioned tables is present since
10.

Author: Nathan Bossart
Reviewed-by: Michael Paquier
Discussion: https://postgr.es/m/DC186201-B01F-4A66-9EC4-F855A957C1F9@amazon.com
2018-08-24 09:15:08 +09:00
Andres Freund 88ebd62fcc Deduplicate code between slot_getallattrs() and slot_getsomeattrs().
Code in slot_getallattrs() is the same as if slot_getsomeattrs() is
called with number of attributes specified in the tuple
descriptor. Implement it that way instead of duplicating the code
between those two functions.

This is part of a patchseries abstracting TupleTableSlots so they can
store arbitrary forms of tuples, but is a nice enough cleanup on its
own.

Author: Ashutosh Bapat
Reviewed-By: Andres Freund
Discussion: https://postgr.es/m/20180220224318.gw4oe5jadhpmcdnm@alap3.anarazel.de
2018-08-23 16:58:53 -07:00
Andrew Gierth a40631a920 Fix lexing of standard multi-character operators in edge cases.
Commits c6b3c939b (which fixed the precedence of >=, <=, <> operators)
and 865f14a2d (which added support for the standard => notation for
named arguments) created a class of lexer tokens which look like
multi-character operators but which have their own token IDs distinct
from Op. However, longest-match rules meant that following any of
these tokens with another operator character, as in (1<>-1), would
cause them to be incorrectly returned as Op.

The error here isn't immediately obvious, because the parser would
usually still find the correct operator via the Op token, but there
were more subtle problems:

1. If immediately followed by a comment or +-, >= <= <> would be given
   the old precedence of Op rather than the correct new precedence;

2. If followed by a comment, != would be returned as Op rather than as
   NOT_EQUAL, causing it not to be found at all;

3. If followed by a comment or +-, the => token for named arguments
   would be lexed as Op, causing the argument to be mis-parsed as a
   simple expression, usually causing an error.

Fix by explicitly checking for the operators in the {operator} code
block in addition to all the existing special cases there.

Backpatch to 9.5 where the problem was introduced.

Analysis and patch by me; review by Tom Lane.
Discussion: https://postgr.es/m/87va851ppl.fsf@news-spur.riddles.org.uk
2018-08-23 21:42:40 +01:00
Andrew Gierth d4a63f8297 Reduce an unnecessary O(N^3) loop in lexer.
The lexer's handling of operators contained an O(N^3) hazard when
dealing with long strings of + or - characters; it seems hard to
prevent this case from being O(N^2), but the additional N multiplier
was not needed.

Backpatch all the way since this has been there since 7.x, and it
presents at least a mild hazard in that trying to do Bind, PREPARE or
EXPLAIN on a hostile query could take excessive time (without
honouring cancels or timeouts) even if the query was never executed.
2018-08-23 21:42:40 +01:00
Tom Lane 5ca0077419 In libpq, don't look up all the hostnames at once.
Historically, we looked up the target hostname in connectDBStart, so that
PQconnectPoll did not need to do DNS name resolution.  The patches that
added multiple-target-host support to libpq preserved this division of
labor; but it's really nonsensical now, because it means that if any one
of the target hosts fails to resolve in DNS, the connection fails.  That
negates the no-single-point-of-failure goal of the feature.  Additionally,
DNS lookups aren't exactly cheap, but the code did them all even if the
first connection attempt succeeds.

Hence, rearrange so that PQconnectPoll does the lookups, and only looks
up a hostname when it's time to try that host.  This does mean that
PQconnectPoll could block on a DNS lookup --- but if you wanted to avoid
that, you should be using hostaddr, as the documentation has always
specified.  It seems fairly unlikely that any applications would really
care whether the lookup occurs inside PQconnectStart or PQconnectPoll.

In addition to calling out that fact explicitly, do some other minor
wordsmithing in the docs around the multiple-target-host feature.

Since this seems like a bug in the multiple-target-host feature,
backpatch to v10 where that was introduced.  In the back branches,
avoid moving any existing fields of struct pg_conn, just in case
any third-party code is looking into that struct.

Tom Lane, reviewed by Fabien Coelho

Discussion: https://postgr.es/m/4913.1533827102@sss.pgh.pa.us
2018-08-23 16:39:36 -04:00
Peter Eisentraut 2d41d914ab Copy-editing of pg_verify_checksums help and ref page
Reformat synopsis, put options into better order, make the desciption
line a bit shorter, and put more details into the description.
2018-08-23 20:32:56 +02:00
Peter Eisentraut d2cc897b3d PL/pgSQL: Extend test case
This test was supposed to check the interaction of INOUT and default
parameters in a procedure call, but it only checked the case where the
parameter was not supplied.  Now it also checks the case where the
parameter was supplied.  It was already working correctly, so no code
changes required.
2018-08-23 17:20:47 +02:00
Alvaro Herrera d10f774165 Return type of txid_status is text, not txid_status
Thinko in commit 857ee8e39.

Discovered-by: Gianni Ciolli
2018-08-23 11:43:36 -03:00
Peter Eisentraut 7ceb6fb84c doc: Clarify some wording in PL/pgSQL about transactions
Some text was still claiming that committing transactions was not
possible in PL/pgSQL.
2018-08-22 15:42:22 +02:00
Peter Eisentraut 0a63f996e0 Change PROCEDURE to FUNCTION in CREATE TRIGGER syntax
Since procedures are now a different thing from functions, change the
CREATE TRIGGER and CREATE EVENT TRIGGER syntax to use FUNCTION in the
clause that specifies the function.  PROCEDURE is still accepted for
compatibility.

pg_dump and ruleutils.c output is not changed yet, because that would
require a change in information_schema.sql and thus a catversion change.

Reported-by: Peter Geoghegan <pg@bowt.ie>
Reviewed-by: Jonathan S. Katz <jonathan.katz@excoventures.com>
2018-08-22 14:44:49 +02:00
Peter Eisentraut d12782898e Change PROCEDURE to FUNCTION in CREATE OPERATOR syntax
Since procedures are now a different thing from functions, change the
CREATE OPERATOR syntax to use FUNCTION in the clause that specifies the
function.  PROCEDURE is still accepted for compatibility.

Reported-by: Peter Geoghegan <pg@bowt.ie>
Reviewed-by: Jonathan S. Katz <jonathan.katz@excoventures.com>
2018-08-22 14:44:49 +02:00
Peter Eisentraut b19495772e doc: Update uses of the word "procedure"
Historically, the term procedure was used as a synonym for function in
Postgres/PostgreSQL.  Now we have procedures as separate objects from
functions, so we need to clean up the documentation to not mix those
terms.

In particular, mentions of "trigger procedures" are changed to "trigger
functions", and access method "support procedures" are changed to
"support functions".  (The latter already used FUNCTION in the SQL
syntax anyway.)  Also, the terminology in the SPI chapter has been
cleaned up.

A few tests, examples, and code comments are also adjusted to be
consistent with documentation changes, but not everything.

Reported-by: Peter Geoghegan <pg@bowt.ie>
Reviewed-by: Jonathan S. Katz <jonathan.katz@excoventures.com>
2018-08-22 14:44:49 +02:00
Thomas Munro af63926cf5 Wrap long line in postgresql.conf.sample.
Per complaint from Michael Paquier.
2018-08-22 21:34:50 +12:00
Thomas Munro f9fe269ca2 Provide plan_cache_mode options in postgresql.conf.sample.
Author: David Rowley
Discussion: https://postgr.es/m/CAKJS1f8YkwojSTSg8YjNYCLCXzx0fR7wBR3Gf%2BrA9_52eoPZKg%40mail.gmail.com
2018-08-22 18:19:39 +12:00
Michael Paquier b965f26171 Do not dump identity sequences with excluded parent table
This commit prevents a crash of pg_dump caused by the exclusion of a
table which has identity columns, as the table would be correctly
excluded but not its identity sequence.  In order to fix that, identity
sequences are excluded if the parent table is defined as such.  Knowing
about such sequences has no meaning without their parent table anyway.

Reported-by: Andy Abelisto
Author: David Rowley
Reviewed-by: Peter Eisentraut, Michael Paquier
Discussion: https://postgr.es/m/153479393218.1316.8472285660264976457@wrigleys.postgresql.org
Backpatch-through: 10
2018-08-22 14:21:49 +09:00
Michael Paquier 98abc73802 Add regression tests for VACUUM and ANALYZE with relation skips
When a user does not have ownership on a relation, then specific log
messages are generated.  This new test suite adds coverage for all the
possible log messages generated, which will be useful to check the
consistency of any refactoring related to ownership checks for relations
vacuumed or analyzed.

Author: Michael Paquier
Reviewed-by: Nathan Bossart
Discussion: https://postgr.es/m/20180812222142.GA6097@paquier.xyz
2018-08-22 09:41:37 +09:00
Alvaro Herrera 55a0154efd Fix typo 2018-08-21 17:16:10 -03:00
Alvaro Herrera 083651da17 fix typo 2018-08-21 17:03:35 -03:00
Alvaro Herrera 69c7890441 Fix typo 2018-08-21 17:00:54 -03:00
Michael Paquier 72be8c29a1 Fix set of NLS translation issues
While monitoring the code, a couple of issues related to string
translation has showed up:
- Some routines for auto-updatable views return an error string, which
sometimes missed the shot.  A comment regarding string translation is
added for each routine to help with future features.
- GSSAPI authentication missed two translations.
- vacuumdb handles non-translated strings.
- GetConfigOptionByNum should translate strings.  This part is not
back-patched as after a minor upgrade this could be surprising for
users.

Reported-by: Kyotaro Horiguchi
Author: Kyotaro Horiguchi
Reviewed-by: Michael Paquier, Tom Lane
Discussion: https://postgr.es/m/20180810.152131.31921918.horiguchi.kyotaro@lab.ntt.co.jp
Backpatch-through: 9.3
2018-08-21 15:17:13 +09:00
Michael Paquier d8c83800c3 Fix typo in description of enable_parallel_hash
Author: Kyotaro Horiguchi
Discussion: https://postgr.es/m/20180821.115841.93250330.horiguchi.kyotaro@lab.ntt.co.jp
2018-08-21 12:13:16 +09:00
Michael Paquier 1339fcc896 Clarify comment about assignment and reset of temp namespace ID in MyProc
The new wording comes from Álvaro, which I modified a bit.

Reported-by: Andres Freund, Álvaro Herrera
Author: Álvaro Herrera, Michael Paquier
Discussion: https://postgr.es/m/20180809165047.GK13638@paquier.xyz
Backpatch-through: 11
2018-08-21 08:32:18 +09:00
Noah Misch f3efef434f MSVC: Finish clean.bat tmp_check coverage.
Use wildcards, so one can add a TAP test suite without updating this
file.  Back-patch to v11, which omitted multiple new suites.
2018-08-19 01:12:22 -07:00
Noah Misch a53f0edd64 MSVC: Remove any tmp_check directory before running a TAP test suite.
Back-patch to v11, where commit 90627cf98a
made the GNU make build system do likewise.  Without this, when a
typical PostgresNode-using test failed, subsequent runs bailed out with
a "File exists" error.
2018-08-19 01:12:22 -07:00
Peter Eisentraut d83423db86 Improve error messages for CREATE OR REPLACE PROCEDURE
Change the hint to recommend DROP PROCEDURE instead of FUNCTION.  Also
make the error message when changing the return type more specific to
the case of procedures.

Reported-by: Jeremy Evans <code@jeremyevans.net>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
2018-08-18 22:05:43 +02:00
Tom Lane 47183265ed Doc: remove obsolete advice about manually inserting snprintf into build.
This para is obsolete, first because nobody is using Solaris 7 anymore,
and second because if someone was, configure should catch the snprintf
buffer overrun problem automatically (since commit 9bed827b1), and third
because this is incorrect advice about how to manually force use of
snprintf.c anyway, and has been so at least since commit 3bc6bdf32.
The lack of complaints about it reinforces the conclusion that Solaris 7
no longer exists in the wild; so I don't feel a need to insert correct
advice instead.
2018-08-18 14:02:35 -04:00
Tom Lane 6771c932cf Ensure schema qualification in pg_restore DISABLE/ENABLE TRIGGER commands.
Previously, this code blindly followed the common coding pattern of
passing PQserverVersion(AH->connection) as the server-version parameter
of fmtQualifiedId.  That works as long as we have a connection; but in
pg_restore with text output, we don't.  Instead we got a zero from
PQserverVersion, which fmtQualifiedId interpreted as "server is too old to
have schemas", and so the name went unqualified.  That still accidentally
managed to work in many cases, which is probably why this ancient bug went
undetected for so long.  It only became obvious in the wake of the changes
to force dump/restore to execute with restricted search_path.

In HEAD/v11, let's deal with this by ripping out fmtQualifiedId's server-
version behavioral dependency, and just making it schema-qualify all the
time.  We no longer support pg_dump from servers old enough to need the
ability to omit schema name, let alone restoring to them.  (Also, the few
callers outside pg_dump already didn't work with pre-schema servers.)

In older branches, that's not an acceptable solution, so instead just
tweak the DISABLE/ENABLE TRIGGER logic to ensure it will schema-qualify
its output regardless of server version.

Per bug #15338 from Oleg somebody.  Back-patch to all supported branches.

Discussion: https://postgr.es/m/153452458706.1316.5328079417086507743@wrigleys.postgresql.org
2018-08-17 17:12:33 -04:00
Peter Eisentraut e4597ee65d InsertPgAttributeTuple() to set attcacheoff
InsertPgAttributeTuple() is the interface between in-memory tuple
descriptors and on-disk pg_attribute, so it makes sense to give it the
job of resetting attcacheoff.  This avoids having all the callers having
to do so.

Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
2018-08-17 22:08:21 +02:00
Andrew Gierth 520acab171 Set scan direction appropriately for SubPlans (bug #15336)
When executing a SubPlan in an expression, the EState's direction
field was left alone, resulting in an attempt to execute the subplan
backwards if it was encountered during a backwards scan of a cursor.
Also, though much less likely, it was possible to reach the execution
of an InitPlan while in backwards-scan state.

Repair by saving/restoring estate->es_direction and forcing forward
scan mode in the relevant places.

Backpatch all the way, since this has been broken since 8.3 (prior to
commit c7ff7663e, SubPlans had their own EStates rather than sharing
the parent plan's, so there was no confusion over scan direction).

Per bug #15336 reported by Vladimir Baranoff; analysis and patch by
me, review by Tom Lane.

Discussion: https://postgr.es/m/153449812167.1304.1741624125628126322@wrigleys.postgresql.org
2018-08-17 15:44:13 +01:00
Tom Lane 9bed827b18 Fix configure's snprintf test so it exposes HP-UX bug.
Since commit e1d19c902, buildfarm member gharial has been failing with
symptoms indicating that snprintf sometimes returns -1 for buffer
overrun, even though it passes the added configure check.  Some
google research suggests that this happens only in limited cases,
such as when the overrun happens partway through a %d item.  Adjust
the configure check to exercise it that way.  Since I'm now feeling
more paranoid than I was before, also make the test explicitly verify
that the buffer doesn't get physically overrun.
2018-08-17 10:38:07 -04:00
Bruce Momjian b94f7b5350 pg_upgrade: issue helpful error message for use on standbys
Commit 777e6ddf17 checked for a shut down
message from a standby and allowed it to continue.  This patch reports a
helpful error message in these cases, suggesting to use rsync as
documented.

Diagnosed-by: Martín Marqués

Discussion: https://postgr.es/m/CAPdiE1xYCow-reLjrhJ9DqrMu-ppNq0ChUUEvVdxhdjGRD5_eA@mail.gmail.com

Backpatch-through: 9.3
2018-08-17 10:25:48 -04:00
Michael Paquier ee80124811 Mention ownership requirements for REFRESH MATERIALIZED VIEW in docs
Author: Dian Fay
Discussion: https://postgr.es/m/745abbd2-a1a0-ead8-2cb2-768c16747d97@gmail.com
Backpatch-through: 9.3
2018-08-17 11:29:15 +09:00
Thomas Munro 96e98fa260 Proof-reading for documentation.
Somebody accidentally a word.  Back-patch to 9.6.

Reported-by: Justin Pryzby
Discussion: https://postgr.es/m/20180816195431.GA23707%40telsasoft.com
2018-08-17 11:36:34 +12:00
Peter Eisentraut 9d0aa4f4d2 Remove unused configure test for ldopen()
unused since f2cc453dd7
2018-08-16 20:05:55 +02:00
Tomas Vondra c4c3400885 Use the built-in float datatypes to implement geometric types
This patch makes the geometric operators and functions use the exported
function of the float4/float8 datatypes.  The main reason of doing so is
to check for underflow and overflow, and to handle NaNs consciously.

The float datatypes consider NaNs values to be equal and greater than
all non-NaN values.  This change considers NaNs equal only for equality
operators.  The placement operators, contains, overlaps, left/right of
etc. continue to return false when NaNs are involved.  We don't need
to worry about them being considered greater than any-NaN because there
aren't any basic comparison operators like less/greater than for the
geometric datatypes.

The changes may be summarised as:

* Check for underflow, overflow and division by zero
* Consider NaN values to be equal
* Return NULL when the distance is NaN for all closest point operators
* Favour not-NaN over NaN where it makes sense

The patch also replaces all occurrences of "double" as "float8".  They
are the same, but were used inconsistently in the same file.

Author: Emre Hasegeli
Reviewed-by: Kyotaro Horiguchi, Tomas Vondra

Discussion: https://www.postgresql.org/message-id/CAE2gYzxF7-5djV6-cEvqQu-fNsnt%3DEqbOURx7ZDg%2BVv6ZMTWbg%40mail.gmail.com
2018-08-16 19:56:11 +02:00