projects / postgresql.git / commitdiff
| author | Bruce Momjian | |
| Tue, 22 Nov 2005 15:13:02 +0000 (15:13 +0000) | ||
| committer | Bruce Momjian | |
| Tue, 22 Nov 2005 15:13:02 +0000 (15:13 +0000) |
| doc/FAQ | patch | blob | blame | history | |
| doc/FAQ_DEV | patch | blob | blame | history | |
| doc/src/FAQ/FAQ.html | patch | blob | blame | history | |
| doc/src/FAQ/FAQ_DEV.html | patch | blob | blame | history |
Last updated: Tue Nov 22 10:04:06 EST 2005
Last updated: Tue Nov 22 10:12:24 EST 2005
Current maintainer: Bruce Momjian ( PostgreSQL is pronounced Post-Gres-Q-L, and is also sometimes If you are looking for a PostgreSQL gatekeeper, central committee, PostgreSQL is distributed under the classic BSD license. Basically, In general, any modern Unix-compatible platform should be able to Via web browser, use The latest release of PostgreSQL is version 8.1.1 We plan to have a major release every year, with minor releases The PostgreSQL community provides assistance to many of its users Visit the PostgreSQL bug form at PostgreSQL supports an extended subset of SQL:2003. PostgreSQL includes extensive documentation, including a large Our web site contains even more documentation. First, consider the PostgreSQL-specific books mentioned above. See the There are several ways of measuring software: features, The PostgreSQL install includes only the C and embedded A nice introduction to Database-backed Web pages can be seen at: For complex cases, many use the Perl and DBD::Pg with CGI.pm or Yes, see Specify the --prefix option when running By default, PostgreSQL only allows connections from the local There are three major areas for potential performance There are many You have reached the default limit is 100 database sessions. You The PostgreSQL team makes only small changes between minor releases, Because PC hardware is mostly compatible, people tend to believe that To retrieve only a few rows, if you know at the number of rows Changing the data type of a column can be done easily in 8.0 You might then want to do VACUUM FULL tab to reclaim the These are the limits: A PostgreSQL database may require up to five times the disk NULLs are stored as bitmaps, so they Indexes are not used by every query. Indexes are used only if the See the EXPLAIN manual page. PostgreSQL supports a SERIAL data type. It One approach is to retrieve the next SERIAL value No. currval() returns the current value assigned by your Every row that is created in PostgreSQL gets a unique You probably have run out of virtual memory on your system, From psql, type Use CURRENT_TIMESTAMP: PostgreSQL supports outer joins using the SQL standard syntax. There is no way to query a database other than the current one. It is easy using set-returning functions, Though "replication" is a single term, there are several technologies There are also commercial and hardware-based replication solutions The most common cause is the use of double-quotes around table or Last updated: Thu Oct 27 09:48:14 EDT 2005 Last updated: Tue Nov 22 10:13:04 EST 2005 Current maintainer: Bruce Momjian ( Download the code and have a look around. See PostgreSQL is developed mostly in the C programming language. It Send an email to pgsql-hackers with a proposal for what you want Generate the patch in contextual diff format. If you are Other than documentation in the source tree itself, you can find There are several ways to obtain the source tree. Occasional Basic system testing First, all the files in the src/tools directory are I have four good books, An Introduction to Database The files configure and configure.in are part of There are a variety of places that need to be modified to add a This was written by Lamar Owen: Of course, there are many projects that DO include all the files This was written by Tom Lane: There are three versions of the SQL standard: SQL-92, SQL:1999, Many technical questions held by those new to the code have been PostgreSQL website development is discussed on the You first need to find the tuples(rows) you are interested in. We do this because this allows a consistent way to pass data The structures passing around from the parser, rewrite, palloc() and pfree() are used in place of malloc() ereport() is used to send messages to the front-end, and Normally, transactions can not see the rows they modify. This First, try running configure with the --enable-cassert "mailto:[email protected]">[email protected])
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referred to as just Postgres. An audio file is available in
http://www.postgresql.org/files/documentation/faqs/FAQ_DEV.html
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or controlling company, give up --- there isn't one. We do have a
Developer's FAQ for information on how to get involved in PostgreSQL
development.)
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PostgreSQL?
UNIVERSITY OF CALIFORNIA HAS NO OBLIGATIONS TO PROVIDE MAINTENANCE,
SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
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run PostgreSQL. The platforms that had received explicit testing at
"http://hobbes.nmsu.edu/cgi-bin/h-search?sh=1&button=Search&key=postgreSQL&stype=all&sort=type&dir=%2F">
http://hobbes.nmsu.edu/cgi-bin/h-search?sh=1&button=Search&key=postgreSQL&stype=all&sort=type&dir=%2F.
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http://www.postgresql.org/ftp/, and via ftp, use
ftp://ftp.PostgreSQL.org/pub/.
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every few months.
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via email. The main web site to subscribe to the email lists is
"http://techdocs.postgresql.org/companies.php">
http://techdocs.postgresql.org/companies.php.
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"http://www.postgresql.org/support/submitbug">
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missing features?
Even the release notes do not contain every change made to the
software.
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manual, manual pages, and some test examples. See the /doc
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SQL?
and at "http://sqlcourse.com/">http://sqlcourse.com.
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team?
Developer's FAQ.
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DBMSs?
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PostgreSQL?
in the Drivers/Interfaces section and via Internet search.
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PostgreSQL with Web pages?
mod_perl.
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interface?
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other than /usr/local/pgsql?
configure.
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hosts?
host-based authentication by modifying the
$PGDATA/pg_hba.conf file, and restart the server.
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better performance?
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available?
log_* server configuration variables that enable printing of query and process statistics which can be
very useful for debugging and performance measurements.
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clients" when trying to connect?
max_connections value in postgresql.conf and
restarting the postmaster.
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to upgrade between major PostgreSQL releases?
data in a generic format that can then be loaded in using the new internal
format.
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all PC hardware is of equal quality. It is not. ECC RAM, SCSI, and
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first few rows of a query? A random row?
LIMIT 1;
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databases, and users are defined? How do I see the queries used
by psql to display them?
illustrates many of the SELECTs needed to get
information from the database system tables.
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and later with ALTER TABLE ALTER COLUMN TYPE.
disk space used by the expired rows.
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table, and a database?
of an MD5 hash of the long column, and full text indexing
allows for searching of words within the column.
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to store data from a typical text file?
use very little space.
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use my indexes?
types exactly match the index's column types. This was particularly
true of int2, int8, and numeric column indexes.
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evaluating my query?
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searches and case-insensitive regular expression searches? How do I
use an index for case-insensitive searches?
case to be stored in the column, use a CHECK
constraint or a trigger.
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is NULL? How can I sort on whether a field is
NULL or not?
ORDER BY (col IS NOT NULL)
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various character types?
particularly values that include NULL bytes. All the
types described here have similar performance characteristics.
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serial/auto-incrementing field?
See the create_sequence manual page for more information
about sequences.
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SERIAL insert?
new_id = execute("SELECT currval('person_id_seq')");
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lead to a race condition with other users?
session, not by all sessions.
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reused on transaction abort? Why are there gaps in the numbering of
my sequence/SERIAL column?
completes. This causes gaps in numbering from aborted
transactions.
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a CTID?
are modified or reloaded. They are used by index entries to point
to physical rows.
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Memory exhausted in AllocSetAlloc()"?
backend is returning too much data, try it before starting the
client.
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I am running?
SELECT version();
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default to the current time?
CREATE TABLE test (x int, modtime TIMESTAMP DEFAULT CURRENT_TIMESTAMP );
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Here are two examples:
RIGHT, and FULL joins. Ordinary joins
are called INNER joins.
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multiple databases?
connections to different databases and merge the results on the
client side.
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columns from a function?
http://techdocs.postgresql.org/guides/SetReturningFunctions.
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does not exist" errors when accessing temporary tables in PL/PgSQL
functions?
EXECUTE for temporary table access in PL/PgSQL. This
will cause the query to be reparsed every time.
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available supporting a variety of replication models.
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recognized in my query?
index 7acb76feb941ad87552267f1d838b19f37be7659..81468b10d195c82197d4f665e29f77d1dc1a3478 100644 (file)
--- a/doc/src/FAQ/FAQ_DEV.html
+++ b/doc/src/FAQ/FAQ_DEV.html
Developer's Frequently Asked Questions (FAQ) for
PostgreSQL
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General Questions
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development?
contributors and core members of the project discuss
development.
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to develop code?
when you make a modification to a C header file, all files depend
upon that file are also rebuilt.
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Outstanding features are detailed in the TODO list. This is located
in doc/TODO in the source distribution or at
"http://www.postgresql.org/docs/faqs.TODO.html">
archives, the SQL standards and the recommend texts (see
"#1.10">1.10).
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work on?
http://momjian.postgresql.org/cgi-bin/pgpatches2.
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unfamiliar with this, you might find the script
that, let us know and we will manually update the documentation when
the patch is applied.
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code?
"http://www.postgresql.org/developer">
http://www.postgresql.org/developer.
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source tree?
"http://developer.postgresql.org/docs/postgres/cvs.html">
http://developer.postgresql.org/docs/postgres/cvs.html.
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you can use the --enable-depend option of configure
to have the compiler compute the dependencies automatically.
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developers?
There is also a script called unused_oids in
pgsql/src/include/catalog that shows the unused oids.
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developers?
on-line written by Jim Gray at
"http://www.benchmarkresources.com">http://www.benchmarkresources.com..
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the GNU autoconf package. Configure allows us to test for
all files derived by configure are removed, so you see only the
file contained in the source distribution.
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new port. First, start in the src/template directory. Add an
handling. There is a backend/port directory if you need
special files for your OS.
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devices, async-I/O, <insert your favorite wizz-bang feature
here>?
cautious about their adoption. The TODO list often contains links
to discussions showing our reasoning in these areas.
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necessary to build RPMs from their Official Tarball (TM).
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dot-release or two, so that we won't have to double-patch the first
wave of fixes.
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standards?
(paper)
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assistance?
questions about development of new features, on IRC at
irc.freenode.net in the #postgresql channel.
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web site development?
Technical Questions
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in tables from the backend code?
ReleaseBuffer(), in the heap_fetch() case. Or it may
be a palloc'ed tuple, that you must pfree() when finished.
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view names sometimes referenced as Name or NameData,
and sometimes as char *?
names(char *), there are many cases where Name and char * are used
interchangeably.
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List to make data structures?
The output appears in the postmaster log file, or on your screen if
you are running a backend directly without a postmaster.
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What else should I do?
places the structure might need code for your new field. mkid
is helpful with this (see
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pfree() to allocate memory?
memory can be allocated in. These affect when the allocated memory
is freed by the backend.
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optionally terminate the current query being processed. The first
descriptors so you don't need to clean these up before the
call.
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allows
UPDATE foo SET x = x + 1 to work correctly. increments the Command Counter, creating a new part of the
transaction.
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available?