Commit Graph

15134 Commits

Author SHA1 Message Date
Michael Paquier 846005e4f3 Relax INSERT privilege requirement for CTAS and matviews WITH NO DATA
When specified, WITH NO DATA does not insert any data into the relation
created, so skip checking for the insert permissions.  With WITH DATA or
WITH NO DATA, it is always required for the user to have CREATE
privileges on the schema targeted for the relation.

Note that plain CREATE TABLE AS or CREATE MATERIALIZED VIEW queries have
begun to work accidentally without INSERT privilege checks as of
874fe3ae, while using EXECUTE or EXPLAIN ANALYZE would fail with the ACL
check, so this makes the behavior for all the command flavors consistent
with each other.  This is arguably a bug fix, but there have been no
complaints about the current behavior either so stable branches are not
changed.

While on it, document properly the privileges requirements for each
commands with more tests for all the scenarios possible, and avoid a
useless bulk-insert allocation when using WITH NO DATA.

Author: Bharath Rupireddy
Reviewed-by: Anastasia Lubennikova, Michael Paquier
Discussion: https://postgr.es/m/CALj2ACWc3N8j0_9nMPz9wcAUnVcdKHzFdDZJ3hVFNEbqtcyG9w@mail.gmail.com
2020-11-16 11:52:40 +09:00
Tom Lane 29d29d652f Fix fuzzy thinking about amcanmulticol versus amcaninclude.
These flags should be independent: in particular an index AM should
be able to say that it supports include columns without necessarily
supporting multiple key columns.  The included-columns patch got
this wrong, possibly aided by the fact that it didn't bother to
update the documentation.

While here, clarify some text about amcanreturn, which was a little
vague about what should happen when amcanreturn reports that only
some of the index columns are returnable.

Noted while reviewing the SP-GiST included-columns patch, which
quite incorrectly (and unsafely) changed SP-GiST to claim
amcanmulticol = true as a workaround for this bug.

Backpatch to v11 where included columns were introduced.
2020-11-15 16:10:58 -05:00
Alexander Korotkov b7edb5d96e Add missing 'the' to pgtrgm.sgml
Author: Erik Rijkers
Discussion: https://postgr.es/m/159fba265fe7c37334640fdc0444cc4b%40xs4all.nl
2020-11-15 14:01:22 +03:00
Alexander Korotkov 935f666650 Handle equality operator in contrib/pg_trgm
Obviously, in order to equality operator be satisfiable, target string must
contain all the trigrams of the search string.  On this base, we implement
equality operator in GiST/GIN indexes with recheck.

Discussion: https://postgr.es/m/CAOBaU_YWwtT7tdggtROacjdOdeYHCz-tmSwuC-j-TOG-g97J0w%40mail.gmail.com
Author: Julien Rouhaud
Reviewed-by: Tom Lane, Alexander Korotkov, Georgios Kokolatos, Erik Rijkers
2020-11-15 08:52:35 +03:00
Tom Lane 92bf7e2d02 Provide the OR REPLACE option for CREATE TRIGGER.
This is mostly straightforward.  However, we disallow replacing
constraint triggers or changing the is-constraint property; perhaps
that can be added later, but the complexity versus benefit tradeoff
doesn't look very good.

Also, no special thought is taken here for whether replacing an
existing trigger should result in changes to queued-but-not-fired
trigger actions.  We just document that if you're surprised by the
results, too bad, don't do that.  (Note that any such pending trigger
activity would have to be within the current session.)

Takamichi Osumi, reviewed at various times by Surafel Temesgen,
Peter Smith, and myself

Discussion: https://postgr.es/m/0DDF369B45A1B44B8A687ED43F06557C010BC362@G01JPEXMBYT03
2020-11-14 17:05:34 -05:00
Tom Lane dbca94510c Doc: improve partitioning discussion in ddl.sgml.
This started with the intent to explain that range upper bounds
are exclusive, which previously you could only find out by reading
the CREATE TABLE man page.  But I soon found that section 5.11
really could stand a fair amount of editorial attention.  It's
apparently been revised several times without much concern for
overall flow, nor careful copy-editing.

Back-patch to v11, which is as far as the patch goes easily.

Per gripe from Edson Richter.  Thanks to David Johnston for review.

Discussion: https://postgr.es/m/DM6PR13MB3988736CF8F5DC5720440231CFE60@DM6PR13MB3988.namprd13.prod.outlook.com
2020-11-14 13:09:53 -05:00
Tom Lane ec0294fb2c Support negative indexes in split_part().
This provides a handy way to get, say, the last field of the string.
Use of a negative index in this way has precedent in the nearby
left() and right() functions.

The implementation scans the string twice when N < -1, but it seems
likely that N = -1 will be the huge majority of actual use cases,
so I'm not really excited about adding complexity to avoid that.

Nikhil Benesch, reviewed by Jacob Champion; cosmetic tweakage by me

Discussion: https://postgr.es/m/cbb7f861-6162-3a51-9823-97bc3aa0b638@gmail.com
2020-11-13 13:49:48 -05:00
Bruce Momjian 152ed04799 doc: clarify where to find pg_type_d.h (PG 11+) and pg_type.h
These files are in compiled directories and install directories.

Reported-by: e.indrupskaya@postgrespro.ru

Discussion: https://postgr.es/m/160379609706.24746.7506163279454026608@wrigleys.postgresql.org

Backpatch-through: 9.5
2020-11-12 15:13:02 -05:00
Bruce Momjian 3370207986 docs: mention that expression indexes need analyze
Expression indexes can't benefit from pre-computed statistics on
columns.

Reported-by: Nikolay Samokhvalov

Discussion: https://postgr.es/m/CANNMO++5rw9RDA=p40iMVbMNPaW6O=S0AFzTU=KpYHRpCd1voA@mail.gmail.com

Author: Nikolay Samokhvalov, modified

Backpatch-through: 9.5
2020-11-12 15:00:44 -05:00
Bruce Momjian 66a8f09048 change wire protocol data type for history file content
This was marked as BYTEA, but is more like TEXT, which is how we already
pass the history timeline file name.  Internally, we don't do any
encoding or bytea escape handling, but TEXT seems closest.  This should
cause no behavioral change.

Reported-by: Brar Piening

Discussion: https://postgr.es/m/6a1b9cd9-17e3-df67-be55-86102af6bdf5@gmx.de

Backpatch-through: master
2020-11-12 14:08:59 -05:00
Heikki Linnakangas 9c4f5192f6 Allow pg_rewind to use a standby server as the source system.
Using a hot standby server as the source has not been possible, because
pg_rewind creates a temporary table in the source system, to hold the
list of file ranges that need to be fetched. Refactor it to queue up the
file fetch requests in pg_rewind's memory, so that the temporary table
is no longer needed.

Also update the logic to compute 'minRecoveryPoint' correctly, when the
source is a standby server.

Reviewed-by: Kyotaro Horiguchi, Soumyadeep Chakraborty
Discussion: https://www.postgresql.org/message-id/0c5b3783-af52-3ee5-f8fa-6e794061f70d%40iki.fi
2020-11-12 14:52:24 +02:00
Bruce Momjian b8b6a0124b doc: fix spelling "connction" to "connection"
Was wrong in commit 1a9388bd0f.

Reported-by: Tom Lane, Justin Pryzby

Discussion: https://postgr.es/m/20201102063333.GE22691@telsasoft.com

Backpatch-through: 9.5
2020-11-10 19:18:35 -05:00
Magnus Hagander d2e4bf688e Remove -o option to postmaster
This option was declared obsolete many years ago.

Reviewed-By: Tom Lane
Discussion: https://postgr.es/m/CABUevEyOE=9CQwZm2j=vwP5+6OLCSoxn9pBjK8gyRdkTzMfqtQ@mail.gmail.com
2020-11-10 13:15:01 +01:00
Tom Lane 24b83a5082 Doc: clarify data type behavior of COALESCE and NULLIF.
After studying the code, NULLIF is a lot more subtle than you might
have guessed.

Discussion: https://postgr.es/m/160486028730.25500.15740897403028593550@wrigleys.postgresql.org
2020-11-09 12:02:46 -05:00
Fujii Masao ef60de67eb doc: Add note about pg_settings and customized options into catalogs.sgml.
The pg_settings view does not display customized options until
the extension module that defines them has been loaded. This commit
add the note about that behavior, into the docs.

Author: John Naylor
Reviewed-by: Tom Lane, Fujii Masao
Discussion: https://postgr.es/m/CAFBsxsGsBZsG=cLM0Op5HFb2Ks6SzJrOc_eRO_jcKSNuqFRKnQ@mail.gmail.com
2020-11-09 15:10:26 +09:00
Peter Eisentraut bdc4edbea6 Move catalog index declarations
Move the system catalog index declarations from catalog/indexing.h to
the respective parent tables' catalog/pg_*.h files.  The original
reason for having it split was that the old genbki system produced the
output in the order of the catalog files it read, so all the indexing
stuff needed to come separately.  But this is no longer the case, and
keeping it together makes more sense.

Reviewed-by: John Naylor <john.naylor@enterprisedb.com>
Discussion: https://www.postgresql.org/message-id/flat/c7cc82d6-f976-75d6-2e3e-b03d2cab26bb@2ndquadrant.com
2020-11-07 12:26:24 +01:00
Peter Eisentraut b4c9695e79 Move catalog toast table declarations
Move the system catalog toast table declarations from
catalog/toasting.h to the respective parent tables' catalog/pg_*.h
files.  The original reason for having it split was that the old
genbki system produced the output in the order of the catalog files it
read, so all the toasting stuff needed to come separately.  But this
is no longer the case, and keeping it together makes more sense.

Reviewed-by: John Naylor <john.naylor@enterprisedb.com>
Discussion: https://www.postgresql.org/message-id/flat/c7cc82d6-f976-75d6-2e3e-b03d2cab26bb@2ndquadrant.com
2020-11-07 12:26:24 +01:00
Tom Lane eeda7f6338 Revert "Accept relations of any kind in LOCK TABLE".
Revert 59ab4ac32, as well as the followup fix 33862cb9c, in all
branches.  We need to think a bit harder about what the behavior
of LOCK TABLE on views should be, and there's no time for that
before next week's releases.  We'll take another crack at this
later.

Discussion: https://postgr.es/m/16703-e348f58aab3cf6cc@postgresql.org
2020-11-06 16:17:56 -05:00
Tom Lane 9e38c2bb50 Declare assorted array functions using anycompatible not anyelement.
Convert array_append, array_prepend, array_cat, array_position,
array_positions, array_remove, array_replace, and width_bucket
to use anycompatiblearray.  This is a simple extension of commit
5c292e6b9 to hit some other places where there's a pretty obvious
gain in usability from doing so.

Ideally we'd also modify other functions taking multiple old-style
polymorphic arguments.  But most of the remainder are tied into one
or more operator classes, making any such change a much larger can of
worms than I desire to open right now.

Discussion: https://postgr.es/m/77675130-89da-dab1-51dd-492c93dcf5d1@postgresfriends.org
2020-11-04 16:09:55 -05:00
Tom Lane 5c292e6b90 Declare lead() and lag() using anycompatible not anyelement.
This allows use of a "default" expression that doesn't slavishly
match the data column's type.  Formerly you got something like
"function lag(numeric, integer, integer) does not exist", which
is not just unhelpful but actively misleading.

The SQL spec suggests that the default should be coerced to the data
column's type, but this implementation instead chooses the common
supertype, which seems at least as reasonable.

(Note: I took the opportunity to run "make reformat-dat-files" on
pg_proc.dat, so this commit includes some cosmetic changes to
recently-added entries that aren't related to lead/lag.)

Vik Fearing

Discussion: https://postgr.es/m/77675130-89da-dab1-51dd-492c93dcf5d1@postgresfriends.org
2020-11-04 15:08:37 -05:00
Michael Paquier e152506ade Revert pg_relation_check_pages()
This reverts the following set of commits, following complaints about
the lack of portability of the central part of the code in bufmgr.c as
well as the use of partition mapping locks during page reads:
c780a7a9
f2b88396
b787d4ce
ce7f772c
60a51c6b

Per discussion with Andres Freund, Robert Haas and myself.

Bump catalog version.

Discussion: https://postgr.es/m/20201029181729.2nrub47u7yqncsv7@alap3.anarazel.de
2020-11-04 10:21:46 +09:00
Tom Lane d907bd0543 Allow users with BYPASSRLS to alter their own passwords.
The intention in commit 491c029db was to require superuserness to
change the BYPASSRLS property, but the actual effect of the coding
in AlterRole() was to require superuserness to change anything at all
about a BYPASSRLS role.  Other properties of a BYPASSRLS role should
be changeable under the same rules as for a normal role, though.

Fix that, and also take care of some documentation omissions related
to BYPASSRLS and REPLICATION role properties.

Tom Lane and Stephen Frost, per bug report from Wolfgang Walther.
Back-patch to all supported branches.

Discussion: https://postgr.es/m/a5548a9f-89ee-3167-129d-162b5985fcf8@technowledgy.de
2020-11-03 15:41:32 -05:00
Peter Eisentraut 2f70fdb064 Remove deprecated containment operators for built-in types
Remove old containment operators @ and ~ for built-in geometry data
types.  These have been deprecated; use <@ and @> instead.

(Some contrib modules still contain the same deprecated operators.
That will be dealt with separately.)

Author: Justin Pryzby <pryzby@telsasoft.com>
Discussion: https://www.postgresql.org/message-id/flat/20201027032511.GF9241@telsasoft.com
2020-11-03 10:43:12 +01:00
Magnus Hagander 5d1833f414 Use be_tls_* API for SSL information in sslinfo
sslinfo was passing the Port->ssl member directly to OpenSSL in order
to extract information regarding the connection. This breaks the API
provided by the backend TLS implementation, as well as duplicates code
for no benefit. Rewrite to make use of the backend API as much as
possible.

Author: Daniel Gustafsson <daniel@yesql.se>
2020-11-03 09:47:36 +01:00
Magnus Hagander 5b3dca096f Clarify temporary table name shadowing in CREATE TABLE docs
Author: David Johnston
2020-11-02 15:00:24 +01:00
Thomas Munro 257836a755 Track collation versions for indexes.
Record the current version of dependent collations in pg_depend when
creating or rebuilding an index.  When accessing the index later, warn
that the index may be corrupted if the current version doesn't match.

Thanks to Douglas Doole, Peter Eisentraut, Christoph Berg, Laurenz Albe,
Michael Paquier, Robert Haas, Tom Lane and others for very helpful
discussion.

Author: Thomas Munro <thomas.munro@gmail.com>
Author: Julien Rouhaud <rjuju123@gmail.com>
Reviewed-by: Peter Eisentraut <peter.eisentraut@2ndquadrant.com> (earlier versions)
Discussion: https://postgr.es/m/CAEepm%3D0uEQCpfq_%2BLYFBdArCe4Ot98t1aR4eYiYTe%3DyavQygiQ%40mail.gmail.com
2020-11-03 01:19:50 +13:00
Thomas Munro cd6f479e79 Add pg_depend.refobjversion.
Provide a place for the version of referenced database objects to be
recorded.  A follow-up commit will use this to record dependencies on
collation versions for indexes, but similar ideas for other kinds of
objects have also been mooted.

Author: Thomas Munro <thomas.munro@gmail.com>
Reviewed-by: Julien Rouhaud <rjuju123@gmail.com>
Reviewed-by: Peter Eisentraut <peter.eisentraut@2ndquadrant.com>
Discussion: https://postgr.es/m/CAEepm%3D0uEQCpfq_%2BLYFBdArCe4Ot98t1aR4eYiYTe%3DyavQygiQ%40mail.gmail.com
2020-11-03 00:44:59 +13:00
Thomas Munro 7d1297df08 Remove pg_collation.collversion.
This model couldn't be extended to cover the default collation, and
didn't have any information about the affected database objects when the
version changed.  Remove, in preparation for a follow-up commit that
will add a new mechanism.

Author: Thomas Munro <thomas.munro@gmail.com>
Reviewed-by: Julien Rouhaud <rjuju123@gmail.com>
Reviewed-by: Peter Eisentraut <peter.eisentraut@2ndquadrant.com>
Discussion: https://postgr.es/m/CAEepm%3D0uEQCpfq_%2BLYFBdArCe4Ot98t1aR4eYiYTe%3DyavQygiQ%40mail.gmail.com
2020-11-03 00:44:59 +13:00
Heikki Linnakangas 8ef2a5afdf doc: Mention UNION/ORDER BY etc. keywords in section headers.
Most of the section and sub-section headers in the Queries chapter have
the keywords literally stated, but neither "Sorting Rows" nor "Combining
Rows" did. There's no rule that they must be, but it seems like a good
practice. The keywords will ring a bell to anyone with with even a little
bit of SQL experience.

David G. Johnston, per suggestion by bilge@scriptfusion.com

Discussion: https://www.postgresql.org/message-id/159981394174.31338.7014519396749859167%40wrigleys.postgresql.org
2020-11-02 12:51:46 +02:00
Michael Paquier 8a15e735be Fix some grammar and typos in comments and docs
The documentation fixes are backpatched down to where they apply.

Author: Justin Pryzby
Discussion: https://postgr.es/m/20201031020801.GD3080@telsasoft.com
Backpatch-through: 9.6
2020-11-02 15:14:41 +09:00
Tom Lane b401fa206d Doc: clarify description for pg_constraint.convalidated.
Jimmy Angelakos

Discussion: https://postgr.es/m/CABgVKCW_zPnvFXn24FTF0299_yU6+1p6JRUc0xpiZFWEXH1_jg@mail.gmail.com
2020-10-30 10:38:49 -04:00
Amit Kapila 8e90ec5580 Track statistics for streaming of changes from ReorderBuffer.
This adds the statistics about transactions streamed to the decoding
output plugin from ReorderBuffer. Users can query the
pg_stat_replication_slots view to check these stats and call
pg_stat_reset_replication_slot to reset the stats of a particular slot.
Users can pass NULL in pg_stat_reset_replication_slot to reset stats of
all the slots.

Commit 9868167500 has added the basic infrastructure to capture the stats
of slot and this commit extends the statistics collector to track
additional information about slots.

Bump the catversion as we have added new columns in the catalog entry.

Author: Ajin Cherian and Amit Kapila
Reviewed-by: Sawada Masahiko and Dilip Kumar
Discussion: https://postgr.es/m/CAA4eK1+chpEomLzgSoky-D31qev19AmECNiEAietPQUGEFhtVA@mail.gmail.com
2020-10-29 09:11:51 +05:30
Tom Lane b787d4ce6d Doc: clean up pg_relation_check_pages() documentation.
Commit f2b883969 did not get the memo about the new formatting
style for tables documenting built-in functions.  I noticed because
of a PDF build warning about an overwidth table.
2020-10-28 17:03:05 -04:00
Tom Lane 4c49d8fc15 Doc: clean up verify_heapam() documentation.
I started with the intention of just suppressing a PDF build warning
by removing the example output, but ended up doing more: correcting
factual errors in the function's signature, moving a bunch of
generalized handwaving into the "Using amcheck Effectively" section
which seemed a better place for it, and improving wording and markup
a little bit.

Discussion: https://postgr.es/m/732904.1603728748@sss.pgh.pa.us
2020-10-28 16:31:40 -04:00
Michael Paquier f2b8839695 Add pg_relation_check_pages() to check on-disk pages of a relation
This makes use of CheckBuffer() introduced in c780a7a, adding a SQL
wrapper able to do checks for all the pages of a relation.  By default,
all the fork types of a relation are checked, and it is possible to
check only a given relation fork.  Note that if the relation given in
input has no physical storage or is temporary, then no errors are
generated, allowing full-database checks when coupled with a simple scan
of pg_class for example.  This is not limited to clusters with data
checksums enabled, as clusters without data checksums can still apply
checks on pages using the page headers or for the case of a page full of
zeros.

This function returns a set of tuples consisting of:
- The physical file where a broken page has been detected (without the
segment number as that can be AM-dependent, which can be guessed from
the block number for heap).  A relative path from PGPATH is used.
- The block number of the broken page.

By default, only superusers have an access to this function but
execution rights can be granted to other users.

The feature introduced here is still minimal, and more improvements
could be done, like:
- Addition of a start and end block number to run checks on a range
of blocks, which would apply only if one fork type is checked.
- Addition of some progress reporting.
- Throttling, with configuration parameters in function input or
potentially some cost-based GUCs.

Regression tests are added for positive cases in the main regression
test suite, and TAP tests are added for cases involving the emulation of
page corruptions.

Bump catalog version.

Author: Julien Rouhaud, Michael Paquier
Reviewed-by: Masahiko Sawada, Justin Pryzby
Discussion: https://postgr.es/m/CAOBaU_aVvMjQn=ge5qPiJOPMmOj5=ii3st5Q0Y+WuLML5sR17w@mail.gmail.com
2020-10-28 12:15:00 +09:00
Amit Kapila 9e0f87a495 Minor improvements in description of spilled counters in pg_stat_replication_slots view.
Per a suggestion by Justin Pryzby.

Discussion: https://postgr.es/m/CA+fd4k5_pPAYRTDrO2PbtTOe0eHQpBvuqmCr8ic39uTNmR49Eg@mail.gmail.com
2020-10-28 07:32:11 +05:30
Tom Lane 8d132b2850 Doc: improve explanation of how to use our code coverage infrastructure.
The reference to running "make coverage" in a subdirectory was a
bit obscure, so clarify what happens when you do that.  Do a little
desultory copy-editing, too.

Per a question from Peter Smith.

Discussion: https://postgr.es/m/CAHut+Pu0r3AjRSyu5E0v2-zRj8r24OSrkWs3fEBxOuaw1i8DKA@mail.gmail.com
2020-10-27 14:31:12 -04:00
Alvaro Herrera 59ab4ac324
Accept relations of any kind in LOCK TABLE
The restriction that only tables and views can be locked by LOCK TABLE
is quite arbitrary, since the underlying mechanism can lock any relation
type.  Drop the restriction so that programs such as pg_dump can lock
all relations they're interested in, preventing schema changes that
could cause a dump to fail after expending much effort.

Backpatch to 9.5.

Author: Álvaro Herrera <alvherre@alvh.no-ip.org>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reported-by: Wells Oliver <wells.oliver@gmail.com>
Discussion: https://postgr.es/m/20201021200659.GA32358@alvherre.pgsql
2020-10-27 13:49:19 -03:00
Bruce Momjian 4066b64290 docs: remove reference to src/tools/thread
This directory and the ability to build the thread test independently
were removed in commit 8a2121185b.

Reported-by: e.indrupskaya@postgrespro.ru

Discussion: https://postgr.es/m/160379609706.24746.7506163279454026608@wrigleys.postgresql.org

Backpatch-through: 9.5
2020-10-27 12:43:11 -04:00
Peter Eisentraut 8fed2eadb8 doc: Fix order of protocol messages in listing
Move GSSENCRequest to the correct alphabetical position.
2020-10-27 08:43:35 +01:00
Amit Kapila 2f0760c9ff Update description of spilled counters in pg_stat_replication_slots view.
This is to make the description of spilled counters clear.

Author: Amit Kapila
Reviewed-by: Sawada Masahiko
Discussion: https://postgr.es/m/CA+fd4k5_pPAYRTDrO2PbtTOe0eHQpBvuqmCr8ic39uTNmR49Eg@mail.gmail.com
2020-10-27 08:22:39 +05:30
Bruce Momjian 2f17fe4318 doc: simplify wording of function error affects
Reported-by: bob.henkel@gmail.com

Discussion: https://postgr.es/m/160324449781.693.8298142858847611071@wrigleys.postgresql.org

Backpatch-through: 9.5
2020-10-26 22:38:11 -04:00
Bruce Momjian e9661f2b0f doc: make blooms docs match reality
Parallel execution changed the way bloom queries are executed, so update
the EXPLAIN output, and restructure the docs to be clearer and more
accurate.

Reported-by: Daniel Westermann

Discussion: https://postgr.es/m/ZR0P278MB0122119FAE78721A694C30C8D2340@ZR0P278MB0122.CHEP278.PROD.OUTLOOK.COM

Author: Daniel Westermann and me

Backpatch-through: 9.6
2020-10-26 19:17:05 -04:00
Heikki Linnakangas fa42c2ecb0 docs: Remove notes about incompatibilies with very old versions.
These are old enough that they'll cause more confusion and distraction
to new readers, than they could help anyone upgrade from very old
servers.

Discussion: https://www.postgresql.org/message-id/fd93f1c5-7818-a02c-01e5-1075ac0d4def%40iki.fi
2020-10-26 09:07:14 +02:00
Tom Lane 1b62d0fb3e Allow psql to re-use connection parameters after a connection loss.
Instead of immediately PQfinish'ing a dead connection, save it aside
so that we can still extract its parameters for \connect attempts.
(This works because PQconninfo doesn't care whether the PGconn is in
CONNECTION_BAD state.)  This allows developers to reconnect with
just \c after a database crash and restart.

It's tempting to use the same approach instead of closing the old
connection after a failed non-interactive \connect command.  However,
that would not be very safe: consider a script containing
	\c db1 user1 live_server
	\c db2 user2 dead_server
	\c db3
The script would be expecting to connect to db3 at dead_server, but
if we re-use parameters from the first connection then it might
successfully connect to db3 at live_server.  This'd defeat the goal
of not letting a script accidentally execute commands against the
wrong database.

Discussion: https://postgr.es/m/38464.1603394584@sss.pgh.pa.us
2020-10-23 17:07:15 -04:00
Peter Eisentraut 83d727e5b2 doc: Fix order of protocol messages in listing
The order of AuthenticationGSSContinue and AuthenticationSSPI was
swapped, based on the other Authentication* protocol messages being
listed in subcode order.
2020-10-23 13:01:39 +02:00
Heikki Linnakangas 902b57c9bf doc: Remove reference to pre-8.2 pg_dump behaviour
The behavioural change in the -t/--table option happened around 15 years
ago and there seems little point in keeping it around.

Author: Ian Barwick
Discussion: https://www.postgresql.org/message-id/CAB8KJ%3Dh-XALik4M7gv-pX48%3D%2BSPWexfaYwa%2ByTnPwD3DxceXrg%40mail.gmail.com
2020-10-23 11:49:59 +03:00
Tom Lane c16a1bbcf4 Add documentation and tests for quote marks in ECPG literal queries.
ECPG's PREPARE ... FROM and EXECUTE IMMEDIATE can optionally take
the target query as a simple literal, rather than the more usual
string-variable reference.  This was previously documented as
being a C string literal, but that's a lie in one critical respect:
you can't write a data double quote as \" in such literals.  That's
because the lexer is in SQL mode at this point, so it'll parse
double-quoted strings as SQL identifiers, within which backslash
is not special, so \" ends the literal.

I looked into making this work as documented, but getting the lexer
to switch behaviors at just the right point is somewhere between
very difficult and impossible.  It's not really worth the trouble,
because these cases are next to useless: if you have a fixed SQL
statement to execute or prepare, you might as well write it as
a direct EXEC SQL, saving the messiness of converting it into
a string literal and gaining the opportunity for compile-time
SQL syntax checking.

Instead, let's just document (and test) the workaround of writing
a double quote as an octal escape (\042) in such cases.

There's no code behavioral change here, so in principle this could
be back-patched, but it's such a niche case I doubt it's worth
the trouble.

Per report from 1250kv.

Discussion: https://postgr.es/m/673825.1603223178@sss.pgh.pa.us
2020-10-22 18:29:46 -04:00
Tom Lane 3dfb1942d9 Avoid premature de-doubling of quote marks in ECPG strings.
If you write the literal 'abc''def' in an EXEC SQL command, that will
come out the other end as 'abc'def', triggering a syntax error in the
backend.  Likewise, "abc""def" is reduced to "abc"def" which is wrong
syntax for a quoted identifier.

The cause is that the lexer thinks it should emit just one quote
mark, whereas what it really should do is keep the string as-is.

Add some docs and test cases, too.

Although this seems clearly a bug, I fear users wouldn't appreciate
changing it in minor releases.  Some may well be working around it
by applying an extra doubling of affected quotes, as for example
sql/dyntest.pgc has been doing.

Per investigation of a report from 1250kv, although this isn't
exactly what he/she was on about.

Discussion: https://postgr.es/m/673825.1603223178@sss.pgh.pa.us
2020-10-22 18:29:46 -04:00
Tom Lane 94929f1cf6 Clean up some unpleasant behaviors in psql's \connect command.
The check for whether to complain about not having an old connection
to get parameters from was seriously out of date: it had not been
rethought when we invented connstrings, nor when we invented the
-reuse-previous option.  Replace it with a check that throws an
error if reuse-previous is active and we lack an old connection to
reuse.  While that doesn't move the goalposts very far in terms of
easing reconnection after a server crash, at least it's consistent.

If the user specifies a connstring plus additional parameters
(which is invalid per the documentation), the extra parameters were
silently ignored.  That seems like it could be really confusing,
so let's throw a syntax error instead.

Teach the connstring code path to re-use the old connection's password
in the same cases as the old-style-syntax code path would, ie if we
are reusing parameters and the values of username, host/hostaddr, and
port are not being changed.  Document this behavior, too, since it was
unmentioned before.  Also simplify the implementation a bit, giving
rise to two new and useful properties: if there's a "password=xxx" in
the connstring, we'll use it not ignore it, and by default (i.e.,
except with --no-password) we will prompt for a password if the
re-used password or connstring password doesn't work.  The previous
code just failed if the re-used password didn't work.

Given the paucity of field complaints about these issues, I don't
think that they rise to the level of back-patchable bug fixes,
and in any case they might represent undesirable behavior changes
in minor releases.  So no back-patch.

Discussion: https://postgr.es/m/235210.1603321144@sss.pgh.pa.us
2020-10-22 14:04:28 -04:00