The new command lists partitioned relations (tables and/or indexes),
possibly with their sizes, possibly including partitioned partitions;
their parents (if not top-level); if indexes show the tables they belong
to; and their descriptions.
While there are various possible improvements to this, having it in this
form is already a great improvement over not having any way to obtain
this report.
Author: Pavel Stěhule, with help from Mathias Brossard, Amit Langote and
Justin Pryzby.
Reviewed-by: Amit Langote, Mathias Brossard, Melanie Plageman,
Michaël Paquier, Álvaro Herrera
This is intended for use mostly in test scripts for external tools,
which could do without cross-PG-version variations in error message
wording. Of course, the SQLSTATE isn't guaranteed stable either, but
it should be more so than the error message text.
Note: there's a bit of an ABI change for libpq here, but it seems
OK because if somebody compiles against a newer version of libpq-fe.h,
and then tries to pass PQERRORS_SQLSTATE to PQsetErrorVerbosity()
of an older libpq library, it will be accepted and then act like
PQERRORS_DEFAULT, thanks to the way the tests in pqBuildErrorMessage3
have historically been phrased. That seems acceptable.
Didier Gautheron, reviewed by Dagfinn Ilmari Mannsåker
Discussion: https://postgr.es/m/CAJRYxuKyj4zA+JGVrtx8OWAuBfE-_wN4sUMK4H49EuPed=mOBw@mail.gmail.com
This introduces the concept of table access methods, i.e. CREATE
ACCESS METHOD ... TYPE TABLE and
CREATE TABLE ... USING (storage-engine).
No table access functionality is delegated to table AMs as of this
commit, that'll be done in following commits.
Subsequent commits will incrementally abstract table access
functionality to be routed through table access methods. That change
is too large to be reviewed & committed at once, so it'll be done
incrementally.
Docs will be updated at the end, as adding them incrementally would
likely make them less coherent, and definitely is a lot more work,
without a lot of benefit.
Table access methods are specified similar to index access methods,
i.e. pg_am.amhandler returns, as INTERNAL, a pointer to a struct with
callbacks. In contrast to index AMs that struct needs to live as long
as a backend, typically that's achieved by just returning a pointer to
a constant struct.
Psql's \d+ now displays a table's access method. That can be disabled
with HIDE_TABLEAM=true, which is mainly useful so regression tests can
be run against different AMs. It's quite possible that this behaviour
still needs to be fine tuned.
For now it's not allowed to set a table AM for a partitioned table, as
we've not resolved how partitions would inherit that. Disallowing
allows us to introduce, if we decide that's the way forward, such a
behaviour without a compatibility break.
Catversion bumped, to add the heap table AM and references to it.
Author: Haribabu Kommi, Andres Freund, Alvaro Herrera, Dimitri Golgov and others
Discussion:
https://postgr.es/m/20180703070645.wchpu5muyto5n647@alap3.anarazel.dehttps://postgr.es/m/20160812231527.GA690404@alvherre.pgsqlhttps://postgr.es/m/20190107235616.6lur25ph22u5u5av@alap3.anarazel.dehttps://postgr.es/m/20190304234700.w5tmhducs5wxgzls@alap3.anarazel.de
latex_escaped_print() mistranslated \ and failed to provide any translation
for # ^ and ~, all of which would typically lead to LaTeX document syntax
errors. In addition it didn't translate < > and |, which would typically
render as unexpected characters.
To some extent this represents shortcomings in ancient versions of LaTeX,
which if memory serves had no easy way to render these control characters
as ASCII text. But that's been fixed for, um, decades. In any case there
is no value in emitting guaranteed-to-fail output for these characters.
Noted while fooling with test cases added by commit 9a98984f4. Back-patch
the code change to all supported versions.
I'd forgotten that in the buildfarm, parts of the regression tests
may run with psql exposed to a non-default LC_NUMERIC setting.
Hence we can't assume that C locale prevails, nor is there any
accessible way to force the setting for this single test step.
Lobotomize the test case added by commit 9a98984f4 so that it covers as
much as we can of print.c without having any locale-varying output.
"\pset format csv", or --csv, selects comma-separated values table format.
This is compliant with RFC 4180, except that we aren't too picky about
whether the record separator is LF or CRLF; also, the user may choose a
field separator other than comma.
This output format is directly compatible with the server's COPY CSV
format, and will also be useful as input to other programs. It's
considerably safer for that purpose than the old recommendation to
use "unaligned" format, since the latter couldn't handle data
containing the field separator character.
Daniel Vérité, reviewed by Fabien Coelho and David Fetter, some
tweaking by me
Discussion: https://postgr.es/m/a8de371e-006f-4f92-ab72-2bbe3ee78f03@manitou-mail.org
As penance for the "\pset format latex" silliness, add some regression
test coverage for the off-the-beaten-path output formats, which formerly
had exactly no coverage, except for some poorly-thought-out (unreadable,
repetitive, and incomplete) tests for asciidoc format.
I make no claims for the behavior exposed here actually being correct;
these test cases are just designed to ensure full code coverage in
fe_utils/print.c. This brings the line coverage for that file up
from ~60% to ~93%.
"\if :{?variable_name}" will be translated to "\if TRUE" if the variable
exists and "\if FALSE" otherwise. Thus it will be possible to execute code
conditionally on the existence of the variable, regardless of its value.
Fabien Coelho, with some review by Robins Tharakan and some light text
editing by me.
Discussion: https://postgr.es/m/alpine.DEB.2.20.1708260835520.3627@lancre
Test queries added by commit 69835bc89 are giving unexpected results
on some smaller buildfarm critters. I think probably the seqscan
logic is kicking in to cause the scans to not start at the beginning
of the table. Add ORDER BY to make them be indexscans instead.
Per buildfarm member chipmunk.
This patch adds ERROR, SQLSTATE, and ROW_COUNT, which are updated after
every query, as well as LAST_ERROR_MESSAGE and LAST_ERROR_SQLSTATE,
which are updated only when a query fails. The expected usage of these
is for scripting.
Fabien Coelho, reviewed by Pavel Stehule
Discussion: https://postgr.es/m/alpine.DEB.2.20.1704042158020.12290@lancre
This command acts somewhat like \g, but instead of executing the query
buffer, it merely prints a description of the columns that the query
result would have. (Of course, this still requires parsing the query;
if parse analysis fails, you get an error anyway.) We accomplish this
using an unnamed prepared statement, which should be invisible to psql
users.
Pavel Stehule, reviewed by Fabien Coelho
Discussion: https://postgr.es/m/CAFj8pRBhYVvO34FU=EKb=nAF5t3b++krKt1FneCmR0kuF5m-QA@mail.gmail.com
In commit e984ef586 I (tgl) simplified the behavior of \p to just print
the current query buffer; but Daniel Vérité points out that this made it
inconsistent with the behavior of \g and \w. It should print the same
thing \g would execute. Fix that, and improve related comments.
Daniel Vérité
Discussion: https://postgr.es/m/9b4ea968-753f-4b5f-b46c-d7d3bf7c8f90@manitou-mail.org
This patch adds nestable conditional blocks to psql. The control
structure feature per se is complete, but the boolean expressions
understood by \if and \elif are pretty primitive; basically, after
variable substitution and backtick expansion, the result has to be
"true" or "false" or one of the other standard spellings of a boolean
value. But that's enough for many purposes, since you can always
do the heavy lifting on the server side; and we can extend it later.
Along the way, pay down some of the technical debt that had built up
around psql/command.c:
* Refactor exec_command() into a function per command, instead of
being a 1500-line monstrosity. This makes the file noticeably longer
because of repetitive function header/trailer overhead, but it seems
much more readable.
* Teach psql_get_variable() and psqlscanslash.l to suppress variable
substitution and backtick expansion on the basis of the conditional
stack state, thereby allowing removal of the OT_NO_EVAL kluge.
* Fix the no-doubt-once-expedient hack of sometimes silently substituting
mainloop.c's previous_buf for query_buf when calling HandleSlashCmds.
(It's a bit remarkable that commands like \r worked at all with that.)
Recall of a previous query is now done explicitly in the slash commands
where that should happen.
Corey Huinker, reviewed by Fabien Coelho, further hacking by me
Discussion: https://postgr.es/m/CADkLM=c94OSRTnat=LX0ivNq4pxDNeoomFfYvBKM5N_xfmLtAA@mail.gmail.com
It can often be useful to use expanded mode output (\x) for just a
single query. Introduce a \gx which acts exactly like \g except that it
will force expanded output mode for that one \gx call. This is simpler
than having to use \x as a toggle and also means that the user doesn't
have to worry about the current state of the expanded variable, or
resetting it later, to ensure a given query is always returned in
expanded mode.
Primairly Christoph's patch, though I did tweak the documentation and help
text a bit, and re-indented the tab completion section.
Author: Christoph Berg
Reviewed By: Daniel Verite
Discussion: https://postgr.es/m/20170127132737.6skslelaf4txs6iw%40msg.credativ.de
This commit improves on the results of commit 511ae628f in two ways:
1. It restores the historical behavior that "\set FOO" is interpreted
as setting FOO to "on", if FOO is a boolean control variable. We
already found one test script that was expecting that behavior, and
the psql documentation certainly does nothing to discourage people
from assuming that would work, since it often says just "if FOO is set"
when describing the effects of a boolean variable. However, now this
case will result in actually setting FOO to "on", not an empty string.
2. It arranges for an "\unset" of a control variable to set the value
back to its default value, rather than becoming apparently undefined.
The control variables are also initialized that way at psql startup.
In combination, these things guarantee that a control variable always
has a displayable value that reflects what psql is actually doing.
That is a pretty substantial usability improvement.
The implementation involves adding a second type of variable hook function
that is able to replace a proposed new value (including NULL) with another
one. We could alternatively have complicated the API of the assign hook,
but this way seems better since many variables can share the same
substitution hook function.
Also document the actual behavior of these variables more fully,
including covering assorted behaviors that were there before but
never documented.
This patch also includes some minor cleanup that should have been in
511ae628f but was missed.
Patch by me, but it owes a lot to discussions with Daniel Vérité.
Discussion: https://postgr.es/m/9572.1485821620@sss.pgh.pa.us
Previously, if the user set a special variable such as ECHO to an
unrecognized value, psql would bleat but store the new value anyway, and
then fall back to a default setting for the behavior controlled by the
variable. This was agreed to be a not particularly good idea. With
this patch, invalid values result in an error message and no change in
state.
(But this applies only to variables that affect psql's behavior; purely
informational variables such as ENCODING can still be set to random
values.)
To do this, modify the API for psql's assign-hook functions so that they
can return an OK/not OK result, and give them the responsibility for
printing error messages when they reject a value. Adjust the APIs for
ParseVariableBool and ParseVariableNum to support the new behavior
conveniently.
In passing, document the variable VERSION, which had somehow escaped that.
And improve the quite-inadequate commenting in psql/variables.c.
Daniel Vérité, reviewed by Rahila Syed, some further tweaking by me
Discussion: https://postgr.es/m/7356e741-fa59-4146-a8eb-cf95fd6b21fb@mm
Upcoming changes to the hash table code used, among others, for grouping
and set operations will change the output order for a few queries. To
make it less likely that actual bugs are hidden between regression test
ordering changes, and to make the tests robust against platform
dependant ordering, add ORDER BYs guaranteeing the output order.
As it's possible that some of the changes expose platform dependant
ordering, push this earlier, to let the buildfarm shake out potentially
unstable results.
Discussion: <20160727004333.r3e2k2y6fvk2ntup@alap3.anarazel.de>
\crosstabview is a completely different way to display results from a
query: instead of a vertical display of rows, the data values are placed
in a grid where the column and row headers come from the data itself,
similar to a spreadsheet.
The sort order of the horizontal header can be specified by using
another column in the query, and the vertical header determines its
ordering from the order in which they appear in the query.
This only allows displaying a single value in each cell. If more than
one value correspond to the same cell, an error is thrown. Merging of
values can be done in the query itself, if necessary. This may be
revisited in the future.
Author: Daniel Verité
Reviewed-by: Pavel Stehule, Dean Rasheed
\gexec executes the just-entered query, like \g, but instead of printing
the results it takes each field as a SQL command to send to the server.
Computing a series of queries to be executed is a fairly common thing,
but up to now you always had to resort to kluges like writing the queries
to a file and then inputting the file. Now it can be done with no
intermediate step.
The implementation is fairly straightforward except for its interaction
with FETCH_COUNT. ExecQueryUsingCursor isn't capable of being called
recursively, and even if it were, its need to create a transaction
block interferes unpleasantly with the desired behavior of \gexec after
a failure of a generated query (i.e., that it can continue). Therefore,
disable use of ExecQueryUsingCursor when doing the master \gexec query.
We can still apply it to individual generated queries, however, and there
might be some value in doing so.
While testing this feature's interaction with single-step mode, I (tgl) was
led to conclude that SendQuery needs to recognize SIGINT (cancel_pressed)
as a negative response to the single-step prompt. Perhaps that's a
back-patchable bug fix, but for now I just included it here.
Corey Huinker, reviewed by Jim Nasby, Daniel Vérité, and myself
This area was rather heavily whacked around in 6513633b9 and follow-on
commits, and it was showing it, because the logic to calculate the
allowable data width in wrapped expanded mode had only the vaguest
relationship to the logic that was actually printing the data. It was
not very close to being right about the conditions requiring overhead
columns to be added. Aside from being wrong, it was pretty unreadable
and under-commented. Rewrite it so it corresponds to what the printing
code actually does.
In passing, remove a couple of dead tests in the printing logic, too.
Per a complaint from Jeff Janes, though this doesn't look much like his
patch because it fixes a number of other corner-case bogosities too.
One such fix that's visible in the regression test results is that
although the code was attempting to enforce a minimum data width of
3 columns, it sometimes left less space than that available.
Remove the code in plpgsql that suppressed the innermost line of CONTEXT
for messages emitted by RAISE commands. That was never more than a quick
backwards-compatibility hack, and it's pretty silly in cases where the
RAISE is nested in several levels of function. What's more, it violated
our design theory that verbosity of error reports should be controlled
on the client side not the server side.
To alleviate the resulting noise increase, introduce a feature in libpq
and psql whereby the CONTEXT field of messages can be suppressed, either
always or only for non-error messages. Printing CONTEXT for errors only
is now their default behavior.
The actual code changes here are pretty small, but the effects on the
regression test outputs are widespread. I had to edit some of the
alternative expected outputs by hand; hopefully the buildfarm will soon
find anything I fat-fingered.
In passing, fix up (again) the output line counts in psql's various
help displays. Add some commentary about how to verify them.
Pavel Stehule, reviewed by Petr Jelínek, Jeevan Chalke, and others
feasible to display tables that have both many columns and some large
data in some columns (such as pg_stats).
Emre Hasegeli with review and rewriting from Sergey Muraviov and
reviewed by Greg Stark
Tom Lane