These APIs changed somewhat subsequent to the initial commit, and may
change further in the future, but let's document what we have today.
KaiGai Kohei and Robert Haas, reviewed by Tom Lane and Thom Brown
BRIN is a new index access method intended to accelerate scans of very
large tables, without the maintenance overhead of btrees or other
traditional indexes. They work by maintaining "summary" data about
block ranges. Bitmap index scans work by reading each summary tuple and
comparing them with the query quals; all pages in the range are returned
in a lossy TID bitmap if the quals are consistent with the values in the
summary tuple, otherwise not. Normal index scans are not supported
because these indexes do not store TIDs.
As new tuples are added into the index, the summary information is
updated (if the block range in which the tuple is added is already
summarized) or not; in the latter case, a subsequent pass of VACUUM or
the brin_summarize_new_values() function will create the summary
information.
For data types with natural 1-D sort orders, the summary info consists
of the maximum and the minimum values of each indexed column within each
page range. This type of operator class we call "Minmax", and we
supply a bunch of them for most data types with B-tree opclasses.
Since the BRIN code is generalized, other approaches are possible for
things such as arrays, geometric types, ranges, etc; even for things
such as enum types we could do something different than minmax with
better results. In this commit I only include minmax.
Catalog version bumped due to new builtin catalog entries.
There's more that could be done here, but this is a good step forwards.
Loosely based on ideas from Simon Riggs; code mostly by Álvaro Herrera,
with contribution by Heikki Linnakangas.
Patch reviewed by: Amit Kapila, Heikki Linnakangas, Robert Haas.
Testing help from Jeff Janes, Erik Rijkers, Emanuel Calvo.
PS:
The research leading to these results has received funding from the
European Union's Seventh Framework Programme (FP7/2007-2013) under
grant agreement n° 318633.
The new format accepts exactly the same data as the json type. However, it is
stored in a format that does not require reparsing the orgiginal text in order
to process it, making it much more suitable for indexing and other operations.
Insignificant whitespace is discarded, and the order of object keys is not
preserved. Neither are duplicate object keys kept - the later value for a given
key is the only one stored.
The new type has all the functions and operators that the json type has,
with the exception of the json generation functions (to_json, json_agg etc.)
and with identical semantics. In addition, there are operator classes for
hash and btree indexing, and two classes for GIN indexing, that have no
equivalent in the json type.
This feature grew out of previous work by Oleg Bartunov and Teodor Sigaev, which
was intended to provide similar facilities to a nested hstore type, but which
in the end proved to have some significant compatibility issues.
Authors: Oleg Bartunov, Teodor Sigaev, Peter Geoghegan and Andrew Dunstan.
Review: Andres Freund
This feature, building on previous commits, allows the write-ahead log
stream to be decoded into a series of logical changes; that is,
inserts, updates, and deletes and the transactions which contain them.
It is capable of handling decoding even across changes to the schema
of the effected tables. The output format is controlled by a
so-called "output plugin"; an example is included. To make use of
this in a real replication system, the output plugin will need to be
modified to produce output in the format appropriate to that system,
and to perform filtering.
Currently, information can be extracted from the logical decoding
system only via SQL; future commits will add the ability to stream
changes via walsender.
Andres Freund, with review and other contributions from many other
people, including Álvaro Herrera, Abhijit Menon-Sen, Peter Gheogegan,
Kevin Grittner, Robert Haas, Heikki Linnakangas, Fujii Masao, Abhijit
Menon-Sen, Michael Paquier, Simon Riggs, Craig Ringer, and Steve
Singer.
The XSLT toolchain requires an empty <index> element where the index is
supposed to appear. Add that with conditionals to hide it from the
DSSSL build.
This program relies on rm_desc backend routines and the xlogreader
infrastructure to emit human-readable rendering of WAL records.
Author: Andres Freund, with many reworks by Álvaro
Reviewed (in a much earlier version) by Peter Eisentraut
There's still a lot of room for improvement, but it basically works,
and we need this to be present before we can do anything much with the
writable-foreign-tables patch. So let's commit it and get on with testing.
Shigeru Hanada, reviewed by KaiGai Kohei and Tom Lane
Background workers are postmaster subprocesses that run arbitrary
user-specified code. They can request shared memory access as well as
backend database connections; or they can just use plain libpq frontend
database connections.
Modules listed in shared_preload_libraries can register background
workers in their _PG_init() function; this is early enough that it's not
necessary to provide an extra GUC option, because the necessary extra
resources can be allocated early on. Modules can install more than one
bgworker, if necessary.
Care is taken that these extra processes do not interfere with other
postmaster tasks: only one such process is started on each ServerLoop
iteration. This means a large number of them could be waiting to be
started up and postmaster is still able to quickly service external
connection requests. Also, shutdown sequence should not be impacted by
a worker process that's reasonably well behaved (i.e. promptly responds
to termination signals.)
The current implementation lets worker processes specify their start
time, i.e. at what point in the server startup process they are to be
started: right after postmaster start (in which case they mustn't ask
for shared memory access), when consistent state has been reached
(useful during recovery in a HOT standby server), or when recovery has
terminated (i.e. when normal backends are allowed).
In case of a bgworker crash, actions to take depend on registration
data: if shared memory was requested, then all other connections are
taken down (as well as other bgworkers), just like it were a regular
backend crashing. The bgworker itself is restarted, too, within a
configurable timeframe (which can be configured to be never).
More features to add to this framework can be imagined without much
effort, and have been discussed, but this seems good enough as a useful
unit already.
An elementary sample module is supplied.
Author: Álvaro Herrera
This patch is loosely based on prior patches submitted by KaiGai Kohei,
and unsubmitted code by Simon Riggs.
Reviewed by: KaiGai Kohei, Markus Wanner, Andres Freund,
Heikki Linnakangas, Simon Riggs, Amit Kapila
They don't actually do anything yet; that will get fixed in a
follow-on commit. But this gets the basic infrastructure in place,
including CREATE/ALTER/DROP EVENT TRIGGER; support for COMMENT,
SECURITY LABEL, and ALTER EXTENSION .. ADD/DROP EVENT TRIGGER;
pg_dump and psql support; and documentation for the anticipated
initial feature set.
Dimitri Fontaine, with review and a bunch of additional hacking by me.
Thom Brown extensively reviewed earlier versions of this patch set,
but there's not a whole lot of that code left in this commit, as it
turns out.
SP-GiST is comparable to GiST in flexibility, but supports non-balanced
partitioned search structures rather than balanced trees. As described at
PGCon 2011, this new indexing structure can beat GiST in both index build
time and query speed for search problems that it is well matched to.
There are a number of areas that could still use improvement, but at this
point the code seems committable.
Teodor Sigaev and Oleg Bartunov, with considerable revisions by Tom Lane
Change range_before, range_after, range_adjacent to return false rather
than throwing an error when one or both input ranges are empty.
The original definition is unnecessarily difficult to use, and also can
result in undesirable planner failures since the planner could try to
compare an empty range to something else while deriving statistical
estimates. (This was, in fact, the cause of repeatable regression test
failures on buildfarm member jaguar, as well as intermittent failures
elsewhere.)
Also tweak rangetypes regression test to not drop all the objects it
creates, so that the final state of the regression database contains
some rangetype objects for pg_dump testing.
This is both very useful in its own right, and an important test case
for the core FDW support.
This commit includes a small refactoring of copy.c to expose its option
checking code as a separately callable function. The original patch
submission duplicated hundreds of lines of that code, which seemed pretty
unmaintainable.
Shigeru Hanada, reviewed by Itagaki Takahiro and Tom Lane
This commit provides the core code and documentation needed. A contrib
module test case will follow shortly.
Shigeru Hanada, Jan Urbanski, Heikki Linnakangas
src/pl/plpgsql/src/plerrcodes.h, src/include/utils/errcodes.h, and a
big chunk of errcodes.sgml are now automatically generated from a single
file, src/backend/utils/errcodes.txt.
Jan Urbański, reviewed by Tom Lane.
This is still pretty rough - among other things, the documentation
needs work, and the messages need a visit from the style police -
but this gets the basic framework in place.
KaiGai Kohei
strength of database passwords, and create a sample implementation of
such a hook as a new contrib module "passwordcheck".
Laurenz Albe, reviewed by Takahiro Itagaki
Set up proper makefile dependencies in the documentation build rules,
especially around the HTML/index build. The problem we've had with all
previous solutions is that we have used the same file name, such as HTML.index
or bookindex.sgml, to mean different things at different stages of the build,
and make can't distinguish that. The solution here is that the first jade run
produces HTML.index, but does not require bookindex.sgml at all, and produces
no other html output (the latter an idea from Alvaro). The second jade run
includes bookindex.sgml, but does not recreate HTML.index. That way, when you
change an sgml file, jade is run twice and at the end all dependencies are
satisfied. Omitting the html output in the first stage also makes the full
build a lot faster.
When you run one of the print format targets, only the first jade run is run,
then the print target-specific commands. If an HTML build has completed
previously, the first jade run is skipped because the dependencies have
already been satisfied.
The draft and check targets for quick builds and syntax verification are still
there.
as per my recent proposal. release.sgml itself is now just a stub that should
change rarely; ideally, only once per major release to add a new include line.
Most editing work will occur in the release-N.N.sgml files. To update a back
branch for a minor release, just copy the appropriate release-N.N.sgml
file(s) into the back branch.
This commit doesn't change the end-product documentation at all, only the
source layout. However, it makes it easy to start omitting ancient information
from newer branches' documentation, should we ever decide to do that.
to ensure that the resulting webpages have predictable URLs, instead of
ever-changing numeric IDs. The new contrib docs were the biggest
offender, but some old stuff had the problem too. Also, rename a couple
of new contrib sgml files for consistency's sake.
pages for the new SQL commands. I also committed Bruce's text search
introductory chapter, as-is except for fixing some markup errors,
so that there would be a place for the reference pages to link to.
language handler to the 'Internals' area, per my proposal of yesterday.
Clean up the trigger documentation a bit. Push SPI chapter to the end
of its part, and reorder the Internals chapters into what seems a more
sensible order (at the moment anyway).
chapters on extending types, operators, and aggregates into the extending
functions chapter. Move the information on how to call table functions
into the queries chapter. Remove some outdated information that is
already present in a better form in other parts of the documentation.
Still needs to be filled with more information, but it gives us a
framework to have a User's Guide with complete coverage of the basic
SQL operations. Move arrays into data type chapter, inheritance into
DDL chapter (for now).
Make <comment>s show up in the output while the version number ends in
"devel".
Allow cross-book references with entities &cite-user; etc.
All of the internal tags are of the latter.
The other thing I noticed is that most of the quick examples in the file
use a para and synopsis. Is there a reason we're not using <example/> ?
Rod Taylor
Remove ODBC-compatible empty parentheses from calls to SQL99 functions
for which these parentheses do not match the standard.
Update the ODBC driver to ensure compatibility with the ODBC standard
for these functions (e.g. CURRENT_TIMESTAMP, CURRENT_USER, etc).
Include a new appendix in the User's Guide which lists the labeled features
for SQL99 (the labeled features replaced the "basic", "intermediate",
and "advanced" categories from SQL92). features.sgml does not yet split
this list into "supported" and "unsupported" lists.
the Admin Guide about routine maintenance tasks. Currently this only
discusses the various reasons for doing VACUUM, but perhaps it could be
fleshed out with topics like log rotation.
Use --enable-nls to turn it on; see installation instructions for details.
See developer's guide how to make use of it in programs and how to add
translations.
psql sources have been almost fully prepared and an incomplete German
translation has been provided. In the backend, only elog() calls are
currently translatable, and the provided German translation file is more
of a placeholder.