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2025-11-06Doc: use uppercase keywords in SQLsDavid Rowley
Use uppercase SQL keywords consistently throughout the documentation to ease reading. Also add whitespace in a couple of places where it improves readability. Author: Erik Wienhold <ewie@ewie.name> Reviewed-by: David Rowley <dgrowleyml@gmail.com> Discussion: https://postgr.es/m/82eb512b-8ed2-46be-b311-54ffd26978c4%40ewie.name
2025-08-21PL/Python: Add event trigger supportPeter Eisentraut
Allow event triggers to be written in PL/Python. It provides a TD dictionary with some information about the event trigger. Author: Euler Taveira <euler@eulerto.com> Co-authored-by: Dimitri Fontaine <dimitri@2ndQuadrant.fr> Reviewed-by: Pavel Stehule <pavel.stehule@gmail.com> Discussion: https://www.postgresql.org/message-id/flat/03f03515-2068-4f5b-b357-8fb540883c38%40app.fastmail.com
2025-06-19doc: add xreflabel text for libpq and PL/PythonBruce Momjian
to be used for PG 18 release notes
2024-11-25doc: Fix example with __next__() in PL/Python functionMichael Paquier
Per PEP 3114, iterator.next() has been renamed to iterator.__next__(), and one example in the documentation still used next(). This caused the example provided to fail the function creation since Python 2 is not supported anymore since 19252e8ec93. Author: Erik Wienhold Discussion: https://postgr.es/m/173209043143.2092749.13692266486972491694@wrigleys.postgresql.org Backpatch-through: 15
2024-01-03Doc: Python's control flow construct is try/except not try/catch.Tom Lane
Very ancient thinko, dating evidently to 22690719e. Spotted by gweatherby. Discussion: https://postgr.es/m/170423637139.1288848.11840082988774620003@wrigleys.postgresql.org
2023-05-02Doc: clarify behavior of row-limit arguments in the PLs' SPI wrappers.Tom Lane
plperl, plpython, and pltcl all provide query-execution functions that are thin wrappers around SPI_execute() or its variants. The SPI functions document their row-count limit arguments clearly, as "maximum number of rows to return, or 0 for no limit". However the PLs' documentation failed to explain this special behavior of zero, so that a reader might well assume it means "fetch zero rows". Improve that. Daniel Gustafsson and Tom Lane, per report from Kieran McCusker Discussion: https://postgr.es/m/CAGgUQ6H6qYScctOhktQ9HLFDDoafBKHyUgJbZ6q_dOApnzNTXg@mail.gmail.com
2023-01-09Doc: add XML ID attributes to <sectN> and <varlistentry> tags.Tom Lane
This doesn't have any external effect at the moment, but it will allow adding useful link-discoverability features later. Brar Piening, reviewed by Karl Pinc. Discussion: https://postgr.es/m/CAB8KJ=jpuQU9QJe4+RgWENrK5g9jhoysMw2nvTN_esoOU0=a_w@mail.gmail.com
2022-03-07plpython: Adjust docs after removal of Python 2 support.Andres Freund
Reviewed-By: Tom Lane <tgl@sss.pgh.pa.us> Discussion: https://postgr.es/m/20211031184548.g4sxfe47n2kyi55r@alap3.anarazel.de
2022-02-02doc: Fix mistake in PL/Python documentationPeter Eisentraut
Small thinko introduced by 94aceed317730953476bec490ce0148b2af3c383 Reported-by: nassehk@gmail.com
2021-06-11Use the correct article for abbreviationsDavid Rowley
We've accumulated quite a mix of instances of "an SQL" and "a SQL" in the documents. It would be good to be a bit more consistent with these. The most recent version of the SQL standard I looked at seems to prefer "an SQL". That seems like a good lead to follow, so here we change all instances of "a SQL" to become "an SQL". Most instances correctly use "an SQL" already, so it also makes sense to use the dominant variation in order to minimise churn. Additionally, there were some other abbreviations that needed to be adjusted. FSM, SSPI, SRF and a few others. Also fix some pronounceable, abbreviations to use "a" instead of "an". For example, "a SASL" instead of "an SASL". Here I've only adjusted the documents and error messages. Many others still exist in source code comments. Translator hint comments seem to be the biggest culprit. It currently does not seem worth the churn to change these. Discussion: https://postgr.es/m/CAApHDvpML27UqFXnrYO1MJddsKVMQoiZisPvsAGhKE_tsKXquw%40mail.gmail.com
2020-12-23dummy commitBruce Momjian
2020-06-11doc: remove xreflabels from commits 75fcdd2ae2 and 85af628da5Bruce Momjian
xreflabels prevent references to the chapter numbers of sections id's. It should only be used in specific cases. Discussion: https://postgr.es/m/8315c0ca-7758-8823-fcb6-f37f9413e6b6@2ndquadrant.com Backpatch-through: 9.5
2020-05-15doc: add missing xreflabels to the main docs (not refs)Bruce Momjian
Add missing xreflabels for index types, geqo, libpq, spi, server-side languages, ecpg, and vaacuumlo. Backpatch-through: 9.5
2020-01-29Invent "trusted" extensions, and remove the pg_pltemplate catalog.Tom Lane
This patch creates a new extension property, "trusted". An extension that's marked that way in its control file can be installed by a non-superuser who has the CREATE privilege on the current database, even if the extension contains objects that normally would have to be created by a superuser. The objects within the extension will (by default) be owned by the bootstrap superuser, but the extension itself will be owned by the calling user. This allows replicating the old behavior around trusted procedural languages, without all the special-case logic in CREATE LANGUAGE. We have, however, chosen to loosen the rules slightly: formerly, only a database owner could take advantage of the special case that allowed installation of a trusted language, but now anyone who has CREATE privilege can do so. Having done that, we can delete the pg_pltemplate catalog, moving the knowledge it contained into the extension script files for the various PLs. This ends up being no change at all for the in-core PLs, but it is a large step forward for external PLs: they can now have the same ease of installation as core PLs do. The old "trusted PL" behavior was only available to PLs that had entries in pg_pltemplate, but now any extension can be marked trusted if appropriate. This also removes one of the stumbling blocks for our Python 2 -> 3 migration, since the association of "plpythonu" with Python 2 is no longer hard-wired into pg_pltemplate's initial contents. Exactly where we go from here on that front remains to be settled, but one problem is fixed. Patch by me, reviewed by Peter Eisentraut, Stephen Frost, and others. Discussion: https://postgr.es/m/5889.1566415762@sss.pgh.pa.us
2020-01-08Remove support for Python older than 2.6Peter Eisentraut
Supporting very old Python versions is a maintenance burden, especially with the several variant test files to maintain for Python <2.6. Since we have dropped support for older OpenSSL versions in 7b283d0e1d1d79bf1c962d790c94d2a53f3bb38a, RHEL 5 is now effectively desupported, and that was also the only mainstream operating system still using Python versions before 2.6, so it's a good time to drop those as well. Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us> Discussion: https://www.postgresql.org/message-id/flat/98b69261-298c-13d2-f34d-836fd9c29b21%402ndquadrant.com
2019-12-31Modernize Python exception syntax in documentationPeter Eisentraut
Change the exception syntax used in the documentation to use the more current except Exception as ex: rather than the old except Exception, ex: We keep the old syntax in the test code since Python <2.6 is still supported there, but the documentation might as well use the modern syntax.
2019-10-25doc: Use proper em and en dashesPeter Eisentraut
2019-09-08doc: Clean up title case usePeter Eisentraut
Note: Following existing practice, titles of formalpara and step are not titlecased.
2018-08-25docs: clarify plpython SD and GD dictionary behaviorBruce Momjian
Reported-by: Adam Bielański Discussion: https://postgr.es/m/153484305538.1370.7605856225879294548@wrigleys.postgresql.org Backpatch-through: 9.3
2018-07-16doc: Update redirecting linksPeter Eisentraut
Update links that resulted in redirects. Most are changes from http to https, but there are also some other minor edits. (There are still some redirects where the target URL looks less elegant than the one we currently have. I have left those as is.)
2018-03-28Allow committing inside cursor loopPeter Eisentraut
Previously, committing or aborting inside a cursor loop was prohibited because that would close and remove the cursor. To allow that, automatically convert such cursors to holdable cursors so they survive commits or rollbacks. Portals now have a new state "auto-held", which means they have been converted automatically from pinned. An auto-held portal is kept on transaction commit or rollback, but is still removed when returning to the main loop on error. This supports all languages that have cursor loop constructs: PL/pgSQL, PL/Python, PL/Perl. Reviewed-by: Ildus Kurbangaliev <i.kurbangaliev@postgrespro.ru>
2018-03-14Support INOUT arguments in proceduresPeter Eisentraut
In a top-level CALL, the values of INOUT arguments will be returned as a result row. In PL/pgSQL, the values are assigned back to the input arguments. In other languages, the same convention as for return a record from a function is used. That does not require any code changes in the PL implementations. Reviewed-by: Pavel Stehule <pavel.stehule@gmail.com>
2018-01-22Transaction control in PL proceduresPeter Eisentraut
In each of the supplied procedural languages (PL/pgSQL, PL/Perl, PL/Python, PL/Tcl), add language-specific commit and rollback functions/commands to control transactions in procedures in that language. Add similar underlying functions to SPI. Some additional cleanup so that transaction commit or abort doesn't blow away data structures still used by the procedure call. Add execution context tracking to CALL and DO statements so that transaction control commands can only be issued in top-level procedure and block calls, not function calls or other procedure or block calls. - SPI Add a new function SPI_connect_ext() that is like SPI_connect() but allows passing option flags. The only option flag right now is SPI_OPT_NONATOMIC. A nonatomic SPI connection can execute transaction control commands, otherwise it's not allowed. This is meant to be passed down from CALL and DO statements which themselves know in which context they are called. A nonatomic SPI connection uses different memory management. A normal SPI connection allocates its memory in TopTransactionContext. For nonatomic connections we use PortalContext instead. As the comment in SPI_connect_ext() (previously SPI_connect()) indicates, one could potentially use PortalContext in all cases, but it seems safest to leave the existing uses alone, because this stuff is complicated enough already. SPI also gets new functions SPI_start_transaction(), SPI_commit(), and SPI_rollback(), which can be used by PLs to implement their transaction control logic. - portalmem.c Some adjustments were made in the code that cleans up portals at transaction abort. The portal code could already handle a command *committing* a transaction and continuing (e.g., VACUUM), but it was not quite prepared for a command *aborting* a transaction and continuing. In AtAbort_Portals(), remove the code that marks an active portal as failed. As the comment there already predicted, this doesn't work if the running command wants to keep running after transaction abort. And it's actually not necessary, because pquery.c is careful to run all portal code in a PG_TRY block and explicitly runs MarkPortalFailed() if there is an exception. So the code in AtAbort_Portals() is never used anyway. In AtAbort_Portals() and AtCleanup_Portals(), we need to be careful not to clean up active portals too much. This mirrors similar code in PreCommit_Portals(). - PL/Perl Gets new functions spi_commit() and spi_rollback() - PL/pgSQL Gets new commands COMMIT and ROLLBACK. Update the PL/SQL porting example in the documentation to reflect that transactions are now possible in procedures. - PL/Python Gets new functions plpy.commit and plpy.rollback. - PL/Tcl Gets new commands commit and rollback. Reviewed-by: Andrew Dunstan <andrew.dunstan@2ndquadrant.com>
2017-11-30SQL proceduresPeter Eisentraut
This adds a new object type "procedure" that is similar to a function but does not have a return type and is invoked by the new CALL statement instead of SELECT or similar. This implementation is aligned with the SQL standard and compatible with or similar to other SQL implementations. This commit adds new commands CALL, CREATE/ALTER/DROP PROCEDURE, as well as ALTER/DROP ROUTINE that can refer to either a function or a procedure (or an aggregate function, as an extension to SQL). There is also support for procedures in various utility commands such as COMMENT and GRANT, as well as support in pg_dump and psql. Support for defining procedures is available in all the languages supplied by the core distribution. While this commit is mainly syntax sugar around existing functionality, future features will rely on having procedures as a separate object type. Reviewed-by: Andrew Dunstan <andrew.dunstan@2ndquadrant.com>
2017-11-23Convert documentation to DocBook XMLPeter Eisentraut
Since some preparation work had already been done, the only source changes left were changing empty-element tags like <xref linkend="foo"> to <xref linkend="foo"/>, and changing the DOCTYPE. The source files are still named *.sgml, but they are actually XML files now. Renaming could be considered later. In the build system, the intermediate step to convert from SGML to XML is removed. Everything is build straight from the source files again. The OpenSP (or the old SP) package is no longer needed. The documentation toolchain instructions are updated and are much simpler now. Peter Eisentraut, Alexander Lakhin, Jürgen Purtz
2017-10-17Don't use SGML empty tagsPeter Eisentraut
For DocBook XML compatibility, don't use SGML empty tags (</>) anymore, replace by the full tag name. Add a warning option to catch future occurrences. Alexander Lakhin, Jürgen Purtz
2017-03-27PL/Python: Add cursor and execute methods to plan objectPeter Eisentraut
Instead of plan = plpy.prepare(...) res = plpy.execute(plan, ...) you can now write plan = plpy.prepare(...) res = plan.execute(...) or even res = plpy.prepare(...).execute(...) and similarly for the cursor() method. This is more in object oriented style, and makes the hybrid nature of the existing execute() function less confusing. Reviewed-by: Andrew Dunstan <andrew.dunstan@2ndquadrant.com>
2017-03-23Remove createlang and droplangPeter Eisentraut
They have been deprecated since PostgreSQL 9.1. Reviewed-by: Magnus Hagander <magnus@hagander.net> Reviewed-by: Daniel Gustafsson <daniel@yesql.se>
2016-10-26Support multi-dimensional arrays in PL/python.Heikki Linnakangas
Multi-dimensional arrays can now be used as arguments to a PL/python function (used to throw an error), and they can be returned as nested Python lists. This makes a backwards-incompatible change to the handling of composite types in arrays. Previously, you could return an array of composite types as "[[col1, col2], [col1, col2]]", but now that is interpreted as a two- dimensional array. Composite types in arrays must now be returned as Python tuples, not lists, to resolve the ambiguity. I.e. "[(col1, col2), (col1, col2)]". To avoid breaking backwards-compatibility, when not necessary, () is still accepted for arrays at the top-level, but it is always treated as a single-dimensional array. Likewise, [] is still accepted for composite types, when they are not in an array. Update the documentation to recommend using [] for arrays, and () for composite types, with a mention that those other things are also accepted in some contexts. This needs to be mentioned in the release notes. Alexey Grishchenko, Dave Cramer and me. Reviewed by Pavel Stehule. Discussion: <CAH38_tmbqwaUyKs9yagyRra=SMaT45FPBxk1pmTYcM0TyXGG7Q@mail.gmail.com>
2016-09-19Remove obsolete warning from docs.Heikki Linnakangas
Python 2.4 and Fedora 4 are both obsolete at this point, especially unpatched debug builds. Discussion: <85e377b2-d459-396e-59b1-115548bbc059@iki.fi>
2016-06-15PL/Python: Clean up extended error reporting docs and testsPeter Eisentraut
Format the example and test code more to Python style standards. Improve whitespace. Improve documentation formatting.
2016-06-11PL/Python: Rename new keyword arguments of plpy.error() etc.Peter Eisentraut
Rename schema -> schema_name etc. to remain consistent with C API and PL/pgSQL.
2016-04-08Enhanced custom error in PLPythonuTeodor Sigaev
Patch adds a new, more rich, way to emit error message or exception from PL/Pythonu code. Author: Pavel Stehule Reviewers: Catalin Iacob, Peter Eisentraut, Jim Nasby
2015-09-01Document that PL/Python now returns floats using repr() not str().Tom Lane
Commit 1ce7a57ca neglected to update the user-facing documentation, which described the old behavior precisely.
2014-11-01PL/Python: Fix examplePeter Eisentraut
Revert "6f6b46c9c0ca3d96acbebc5499c32ee6369e1eec", which was broken. Reported-by: Jonathan Rogers <jrogers@socialserve.com>
2014-07-03Improve support for composite types in PL/Python.Tom Lane
Allow PL/Python functions to return arrays of composite types. Also, fix the restriction that plpy.prepare/plpy.execute couldn't handle query parameters or result columns of composite types. In passing, adopt a saner arrangement for where to release the tupledesc reference counts acquired via lookup_rowtype_tupdesc. The callers of PLyObject_ToCompositeDatum were doing the lookups, but then the releases happened somewhere down inside subroutines of PLyObject_ToCompositeDatum, which is bizarre and bug-prone. Instead release in the same function that acquires the refcount. Ed Behn and Ronan Dunklau, reviewed by Abhijit Menon-Sen
2014-02-24docs: remove unnecessary references to old PG versionsBruce Momjian
2013-07-05PL/Python: Convert numeric to DecimalPeter Eisentraut
The old implementation converted PostgreSQL numeric to Python float, which was always considered a shortcoming. Now numeric is converted to the Python Decimal object. Either the external cdecimal module or the standard library decimal module are supported. From: Szymon Guz <mabewlun@gmail.com> From: Ronan Dunklau <rdunklau@gmail.com> Reviewed-by: Steve Singer <steve@ssinger.info>
2013-02-03PL/Python: Add result object str handlerPeter Eisentraut
This is intended so that say plpy.debug(rv) prints something useful for debugging query execution results. reviewed by Steve Singer
2012-09-29PL/Python: Convert oid to long/intPeter Eisentraut
oid is a numeric type, so transform it to the appropriate Python numeric type like the other ones.
2012-07-14Add link to PEP 394 regarding python2 vs python3 namingPeter Eisentraut
2012-04-28PL/Python: Update list of supported environment variablesPeter Eisentraut
2012-04-16PL/Python: Improve documentation of nrows() methodPeter Eisentraut
Clarify that nrows() is the number of rows processed, versus the number of rows returned, which can be obtained using len. Also add tests about that.
2012-04-15PL/Python: Fix crash when colnames() etc. called without result setPeter Eisentraut
The result object methods colnames() etc. would crash when called after a command that did not produce a result set. Now they throw an exception. discovery and initial patch by Jean-Baptiste Quenot
2012-03-26Improve PL/Python database access function documentationPeter Eisentraut
Organize the function descriptions as a list instead of running text, for easier access.
2012-01-30PL/Python: Add result metadata functionsPeter Eisentraut
Add result object functions .colnames, .coltypes, .coltypmods to obtain information about the result column names and types, which was previously not possible in the PL/Python SPI interface. reviewed by Abhijit Menon-Sen
2012-01-18PL/Python: Update examplePeter Eisentraut
Change the usesavedplan() example to use a more modern Python style using the .setdefault() function.
2011-12-05plpython: Add SPI cursor supportPeter Eisentraut
Add a function plpy.cursor that is similar to plpy.execute but uses an SPI cursor to avoid fetching the entire result set into memory. Jan Urbański, reviewed by Steve Singer
2011-06-04Fix documentation reference to "above" examplePeter Eisentraut
found by Thom Brown
2011-05-19Spell checking and markup refinementPeter Eisentraut