Frequently Asked Questions (FAQ) for PostgreSQL
- Last updated: Fri Mar 12 08:51:11 EST 2004
+ Last updated: Mon Mar 29 00:07:11 EST 2004
Current maintainer: Bruce Momjian (pgman@candle.pha.pa.us)
1.1) What is PostgreSQL? How is it pronounced?
- PostgreSQL is pronounced Post-Gres-Q-L. The name "Postgres" is also
- used in conversation.
+ PostgreSQL is pronounced Post-Gres-Q-L. An audio file is available at
+ http://www.postgresql.org/postgresql.mp3 for those would like to hear
+ the pronunciation.
PostgreSQL is an enhancement of the POSTGRES database management
- system, a next-generation DBMS research prototype. While PostgreSQL
- retains the powerful data model and rich data types of POSTGRES, it
- replaces the PostQuel query language with an extended subset of SQL.
- PostgreSQL is free and the complete source is available.
+ system (and is still sometimes reffered to as simply "Postgres"), a
+ next-generation DBMS research prototype. While PostgreSQL retains the
+ powerful data model and rich data types of POSTGRES, it replaces the
+ PostQuel query language with an extended subset of SQL. PostgreSQL is
+ free and the complete source is available.
PostgreSQL development is performed by a team of developers who all
subscribe to the PostgreSQL development mailing list. The current
coordinator is Marc G. Fournier (scrappy@PostgreSQL.org). (See section
1.6 on how to join). This team is now responsible for all development
of PostgreSQL. It is a community project and is not controlled by any
- company. To get involved, see the developer's
- FAQ,http://www.PostgreSQL.org/docs/faqs/FAQ_DEV.html
+ company. To get involved, see the developer's FAQ at
+ http://www.PostgreSQL.org/docs/faqs/FAQ_DEV.html
The authors of PostgreSQL 1.01 were Andrew Yu and Jolly Chen. Many
others have contributed to the porting, testing, debugging, and
PostgreSQL Data Base Management System
- Portions copyright (c) 1996-2002, PostgreSQL Global Development Group
+ Portions copyright (c) 1996-2004, PostgreSQL Global Development Group
Portions Copyright (c) 1994-6 Regents of the University of California
Permission to use, copy, modify, and distribute this software and its
1.3) What Unix platforms does PostgreSQL run on?
- In general, a modern Unix-compatible platform should be able to run
+ In general, any modern Unix-compatible platform should be able to run
PostgreSQL. The platforms that had received explicit testing at the
time of release are listed in the installation instructions.
These include PgAccess http://www.pgaccess.org), PgAdmin III
(http://www.pgadmin.org, RHDB Admin (http://sources.redhat.com/rhdb/ )
and Rekall ( http://www.thekompany.com/products/rekall/, proprietary).
- There is also PHPPgAdmin ( http://phppgadmin.sourceforge.net/ ), a
+ There is also PhpPgAdmin ( http://phppgadmin.sourceforge.net/ ), a
web-based interface to PostgreSQL.
See http://techdocs.postgresql.org/guides/GUITools for a more detailed
By default, PostgreSQL only allows connections from the local machine
using Unix domain sockets. Other machines will not be able to connect
- unless you add the -i flag to postmaster, and enable host-based
- authentication by modifying the file $PGDATA/pg_hba.conf accordingly.
- This will allow TCP/IP connections.
+ unless you turn on tcpip_sockets in the postgresql.conf and enable
+ host-based authentication by modifying the file $PGDATA/pg_hba.conf
+ accordingly. This will allow TCP/IP connections.
3.6) How do I tune the database engine for better performance?
- Certainly, indexes can speed up queries. The EXPLAIN command allows
- you to see how PostgreSQL is interpreting your query, and which
+ Certainly, indexes can speed up queries. The EXPLAIN ANALYZE command
+ allows you to see how PostgreSQL is interpreting your query, and which
indexes are being used.
If you are doing many INSERTs, consider doing them in a large batch
4.3) How do I get a list of tables or other things I can see in psql?
- You can read the source code for psql in file
- pgsql/src/bin/psql/describe.c. It contains SQL commands that generate
- the output for psql's backslash commands. You can also start psql with
- the -E option so it will print out the queries it uses to execute the
- commands you give.
+ Use the \dt command to see tables in psql. For a complete list of
+ commands inside psql you can use \?. Alternatively you can read the
+ source code for psql in file pgsql/src/bin/psql/describe.c, it
+ contains SQL commands that generate the output for psql's backslash
+ commands. You can also start psql with the -E option so it will print
+ out the queries it uses to execute the commands you give. PostgreSQL
+ also provides an SQLi compliant INFORMATION SCHEMA interface you can
+ query to get information about the database.
4.4) How do you remove a column from a table, or change its data type?
projects / postgresql / blobdiff