Frequently Asked Questions (FAQ) for PostgreSQL
- Last updated: Sat Feb 28 10:04:28 EST 1998
+ Last updated: Wed Apr 15 12:47:01 EDT 1998
Current maintainer: Bruce Momjian (maillist@candle.pha.pa.us)
1.12) What tools are available for hooking PostgreSQL to Web pages?
1.13) Does PostgreSQL have a graphical user interface? A report
generator? A embedded query language interface?
- 1.14) What is a good book to learn SQL?
+ 1.14) How can I learn SQL?
1.15) What languages are available to communicate with PostgreSQL?
2) Installation/Configuration questions
2.10) All my servers crash under concurrent table access. Why?
2.11) How do I tune the database engine for better performance?
2.12) What debugging features are available in PostgreSQL?
- 2.13) How do I enable more than 32 concurrent backends?
+ 2.13) How do I enable more than 32 concurrent backends? 2.14) What
+ non-unix ports are available?
3) Operational questions
1.6) Latest release of PostgreSQL
- The latest release of PostgreSQL is version 6.3, which was released on
- March 1st, 1998.
+ The latest release of PostgreSQL is version 6.3.2.
We plan to have major releases every three months.
1.8) What documentation is available for PostgreSQL?
A user manual, manual pages, and some small test examples are included
- in the distribution. The sql and built-in manual pages are
- particularly important.
+ in the distribution. The pgintro, sql, and pgbuiltin manual pages are
+ particularly important. pgintro contains a list of all available
+ manual pages.
+
+ psql has some nice \d commands to show information about types,
+ operators, functions, aggregates, etc.
The www page contains pointers to an implementation guide and five
papers written about Postgres design concepts and features.
1.9) What version of SQL does PostgreSQL use?
- PostgreSQL supports a subset of SQL-92. It has most of the important
- constructs but lacks some of the functionality. The most visible
- differences are:
- * no HAVING clause under a GROUP BY
-
- On the other hand, you get to create user-defined types, functions,
- inheritance etc.
+ PostgreSQL supports a subset of SQL-92.
1.10) Does PostgreSQL work with databases from earlier versions of
PostgreSQL?
Those ugrading from versions earlier than 1.09 must upgrade to 1.09
first without a dump/reload, then dump the data from 1.09, and then
- load it into 6.2.1 or 6.3 beta.
+ load it into 6.2.1 or 6.3.
1.11) Are there ODBC drivers for PostgreSQL?
* majordomo@listserv.direct.net
OpenLink ODBC is very popular. You can get it from
- http://www.openlinksw.com/postgres.html. It works with our standard
- ODBC client software so you'll have PostgreSQL ODBC available on every
- client platform we support (Win, Mac, Unix, VMS).
+ http://www.openlinksw.com. It works with our standard ODBC client
+ software so you'll have PostgreSQL ODBC available on every client
+ platform we support (Win, Mac, Unix, VMS).
We will probably be selling this product to people who need
commercial-quality support, but a freeware version will always be
We also have ecpg, which is an embedded SQL query language interface
for C. This is also included.
- 1.14) What is a good book to learn SQL?
+ 1.14) How can I learn SQL?
+ There is a nice tutorial at http://w3.one.net/~jhoffman/sqltut.htm
Many of our users like The Practical SQL Handbook, Bowman et al,
Addison Wesley.
2.11) How do I tune the database engine for better performance?
- There are two things that can be done. You can disable fsync() by
+ There are several things that can be done. You can disable fsync() by
starting the postmaster with a '-o -F' option. This will prevent
fsync()'s from flushing to disk after every transaction.
of memory used by each backend process for temporary sorts. Each
buffer is 1K and the defualt is 512 buffers.
+ You can also use the CLUSTER command to group data in base tables to
+ match an index. See the cluster(l) manual page for more details.
+
2.12) What debugging features are available in PostgreSQL?
PostgreSQL has several features that report status information that
Edit include/storage/sinvaladt.h, and change the value of
MaxBackendId. In the future, we plan to make this a configurable
prameter.
+
+ 2.13) What non-unix ports are available?
+
+ It is possible to compile the libpq C library, psql, and other
+ interfaces and binaries to run on MS Windows platforms. In this case,
+ the client is running on MS Windows, and communicates via TCP/IP to a
+ server running on one of our supported Unix platforms.
+
+ People have attempted to port our PostgreSQL database server to
+ Windows NT using the Cygnus Unix/NT porting library, but no one has
+ succeeded yet.
_________________________________________________________________
Section 3: PostgreSQL Features
3.10) How do I do regular expression searches? case-insensitive regexp
searching?
- See the pgbuiltin manual page. Search for regular expression.
+ See psql's \do command.
3.11) I experienced a server crash during a vacuum. How do I remove the lock
file?
The default configuration allows only unix domain socket connections
from the local machine. To enable TCP/IP connections, use the
postmaster -i option You need to add a host entry to the file
- pgsql/data/pg_hba. See the hba_conf manual page.
+ pgsql/data/pg_hba. See the pg_hba.conf manual page.
3.18) How do I find out what indexes or operations are defined in the
database?