From f0410b1e12ece0230d686cf4abfb5dfbf9631dab Mon Sep 17 00:00:00 2001 From: Bruce Momjian Date: Fri, 27 Feb 1998 22:01:58 +0000 Subject: [PATCH] Prepare for final release. --- HISTORY | 25 +- doc/FAQ | 1578 ++++++++++++++++++++++------------------ doc/TODO | 250 +++---- migration/6.2.1_to_6.3 | 65 +- register.txt | 2 +- 5 files changed, 1063 insertions(+), 857 deletions(-) diff --git a/HISTORY b/HISTORY index 83ad2f135b..802c1ffeaa 100644 --- a/HISTORY +++ b/HISTORY @@ -1,4 +1,4 @@ -PostgreSQL 6.3 Sun Feb 1 14:57:30 EST 1998 +PostgreSQL 6.3 Sun Mar 1 14:57:30 EST 1998 ------------------------------------------------------------- A dump/restore is required for those wishing to migrate data from @@ -39,16 +39,16 @@ Generate elog(ERROR) on over-large integer(Bruce) Allow multiple-argument functions in constraint clauses(Thomas) Check boolean input literals for 'true','false','yes','no','1','0' and throw elog(ERROR) if unrecognized(Thomas) -Change default table creation from ACL_RD to ACL_NO (aka private tables)(marc) - +Major large objects fix Enhancements ------------ +Subselects with EXISTS, IN, ALL, ANY keywords (Vadim, Bruce, Thomas) +New User Manual(Thomas, others) +Speedup by inlining some frequently-called functions Real deadlock detection, no more timeouts(Bruce) - Subselects with EXISTS, IN, ALL, ANY keywords (Vadim, Bruce, Thomas) Add SQL92 "constants" CURRENT_DATE, CURRENT_TIME, CURRENT_TIMESTAMP, CURRENT_USER(Thomas) -Speedup by inlining some frequently-called functions Modify constraint syntax to be SQL92-compliant(Thomas) Implement SQL92 PRIMARY KEY and UNIQUE clauses using indices(Thomas) Recognize SQL92 syntax for FOREIGN KEY. Throw elog notice(Thomas) @@ -107,7 +107,6 @@ Add UNION, GROUP, DISTINCT to INSERT(Bruce) varchar() stores only necessary bytes on disk(Bruce) Fix for BLOBs(Peter) Mega-Patch for JDBC...see README_6.3 for list of changes(Peter) -Allow installation data block size and max tuple size configuration(Darren) Remove unused "option" from PQconnectdb() New LOCK command and lock manual page describing deadlocks(Bruce) Add new psql \da, \dd, \df, \do, \dS, and \dT commands(Bruce) @@ -122,8 +121,17 @@ Add Unix socket support to DBD::Pg(Goran) New python interface (PyGreSQL 2.0)(D'Arcy) New frontend/backend protocol has a version number, network byte order(Phil) Security features in pg_hba.conf enhanced and documented, many cleanups(Phil) -New HTML and Postscript documentation(Thomas) - +CHAR() now faster access than VARCHAR() or TEXT +ecpg embedded SQL preprocessor +Add GROUP BY to INSERT INTO table SELECT * FROM table2 +Reduce system column overhead(Vadmin) +Remove pg_time table(Vadim) +Add pg_type attribute to identify types that need length (bpchar, varchar) +Add report of offending line when COPY command fails +Allow VIEW permissions to be set separately from the underlying tables. + For security, use GRANT/REVOKE on views as appropriate(Jan) +Tables now have no default GRANT SELECT TO PUBLIC. You must + explicitly grant such permissions. Source Tree Changes ------------------- @@ -160,6 +168,7 @@ Start an AUX port Start a Cygnus port Add string functions to regression suite(Thomas) Expand a few function names formerly truncated to 16 characters(Thomas) +Remove un-needed malloc() calls and replace with palloc()(Bruce) PostgreSQL 6.2.1 Fri Oct 17 00:01:27 EDT 1997 diff --git a/doc/FAQ b/doc/FAQ index 45d02f19ac..c51c676f3e 100644 --- a/doc/FAQ +++ b/doc/FAQ @@ -1,587 +1,717 @@ + + +PostgreSQL FAQ + + +

Frequently Asked Questions (FAQ) for PostgreSQL - -Last updated: Sun Feb 1 16:13:28 EST 1998 - -Current maintainer: Bruce Momjian (maillist@candle.pha.pa.us) - -The most recent version of this document can be viewed at the postgreSQL Web -site, http://postgreSQL.org. - +

+

+Last updated: Wed Feb 25 14:37:07 EST 1998 +

+Current maintainer: Bruce Momjian (maillist@candle.pha.pa.us)
+

+The most recent version of this document can be viewed at +the postgreSQL Web site, http://postgreSQL.org. +

Linux-specific questions are answered in -http://postgreSQL.org/docs/faq-linux.shtml. - +http://postgreSQL.org/docs +/faq-linux.shtml. +

Irix-specific questions are answered in -http://postgreSQL.org/docs/faq-irix.shtml. +http://postgreSQL.org/docs/ +faq-irix.shtml. +

+

+

+

Questions answered:

+

1) General questions

+1.1) What is PostgreSQL?
+1.2) What does PostgreSQL run on?
+1.3) Where can I get PostgreSQL?
+1.4) What's the copyright on PostgreSQL?
+1.5) Support for PostgreSQL
+1.6) Latest release of PostgreSQL
+1.7) Is there a commercial version of PostgreSQL?
+1.8) What documentation is available for PostgreSQL?
+1.9) What version of SQL does PostgreSQL use?
+1.10) Does PostgreSQL work with databases from +earlier versions of postgres?
+1.11) Are there ODBC drivers for +PostgreSQL?
+1.12) What tools are available for hooking +postgres 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?
- ------------------------------------------------------------------------ +

2) Installation/Configuration questions

+2.1) initdb doesn't run
+2.2) when I start up the postmaster, I get + "FindBackend: could not find a backend to execute..." + "postmaster: could not find backend to execute..."
+2.3) The system seems to be confused about commas, +decimal points, and date formats.
+2.4) How do I install PostgreSQL somewhere other than +/usr/local/pgsql?
+2.5) When I run postmaster, I get a Bad System Call +core dumped message.
+2.6) When I try to start the postmaster, I get +IpcMemoryCreate errors.
+2.7) I have changed a source file, but a +recompile does not see the change?
+2.8) How do I prevent other hosts from accessing my +PostgreSQL
+2.9) I can't access the database as the +'root' user.
+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? +

3) Operational questions

+3.1) Does PostgreSQL support nested subqueries?
+3.2) I've having a lot of problems using rules.
+3.3) I can't seem to write into the middle of large +objects reliably.
+3.4) How can I write client applications to +PostgreSQL?
+3.5) How do I set up a pg_group?
+3.6) What is the exact difference between +binary cursors and normal cursors?
+3.7) What is a R-tree index and what is it +used for?
+3.8) What is the maximum size for a +tuple?
+3.9) I defined indices but my queries don't +seem to make use of them. Why?
+3.10) How do I do regular expression searches? +case-insensitive regexp searching?
+3.11) I experienced a server crash during a +vacuum. How do I remove the lock file?
+3.12) What is the difference between the +various character types?
+3.13) In a query, how do I detect if a field +is NULL?
+3.14) How do I see how the query optimizer is +evaluating my query?
+3.15) How do I create a serial field?
+3.16) What are the pg_psort.XXX files in my +database directory?
+3.17) Why can't I connect to my database from +another machine?
+3.18) How do I find out what indexes or +operations are defined in the database?
+3.19) What is the time-warp feature and how +does it relate to vacuum?
+3.20) What is an oid? What is a tid?
+3.21) What is the meaning of some of the terms +used in Postgres?
+3.22) What is Genetic Query Optimization?
+3.23) How do you remove a column from a table?
+3.24) How do SELECT only the first few rows of +a query?
+3.25) Why can't I create a column named "time"?
+3.26) How much database disk space is required +to store data from a typical flat file?
+

4) Questions about extending PostgreSQL

+4.1) I wrote a user-defined function and when I run +it in psql, it dumps core.
+4.2) I get messages of the type +NOTICE:PortalHeapMemoryFree: 0x402251d0
+4.3) I've written some nifty new types and functions +for PostgreSQL.
+4.4) How do I write a C function to return a +tuple?
+

5) Bugs

+5.1) How do I make a bug report? +

-Questions answered: - -1) General questions - -1.1) What is PostgreSQL? -1.2) What does PostgreSQL run on? -1.3) Where can I get PostgreSQL? -1.4) What's the copyright on PostgreSQL? -1.5) Support for PostgreSQL -1.6) Latest release of PostgreSQL -1.7) Is there a commercial version of PostgreSQL? -1.8) What documentation is available for PostgreSQL? -1.9) What version of SQL does PostgreSQL use? -1.10) Does PostgreSQL work with databases from earlier versions of postgres? -1.11) Are there ODBC drivers for PostgreSQL? -1.12) What tools are available for hooking postgres 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? - -2) Installation/Configuration questions - -2.1) initdb doesn't run -2.2) when I start up the postmaster, I get "FindBackend: could not find a -backend to execute..." "postmaster: could not find backend to execute..." -2.3) The system seems to be confused about commas, decimal points, and date -formats. -2.4) How do I install PostgreSQL somewhere other than /usr/local/pgsql? -2.5) When I run postmaster, I get a Bad System Call core dumped message. -2.6) When I try to start the postmaster, I get IpcMemoryCreate errors. -2.7) I have changed a source file, but a recompile does not see the change? -2.8) How do I prevent other hosts from accessing my PostgreSQL -2.9) I can't access the database as the 'root' user. -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? - -3) Operational questions - -3.1) Does PostgreSQL support nested subqueries? -3.2) I've having a lot of problems using rules. -3.3) I can't seem to write into the middle of large objects reliably. -3.4) How can I write client applications to PostgreSQL? -3.5) How do I set up a pg_group? -3.6) What is the exact difference between binary cursors and normal cursors? -3.7) What is a R-tree index and what is it used for? -3.8) What is the maximum size for a tuple? -3.9) I defined indices but my queries don't seem to make use of them. Why? -3.10) How do I do regular expression searches? case-insensitive regexp -searching? -3.11) I experienced a server crash during a vacuum. How do I remove the lock -file? -3.12) What is the difference between the various character types? -3.13) In a query, how do I detect if a field is NULL? -3.14) How do I see how the query optimizer is evaluating my query? -3.15) How do I create a serial field? -3.16) What are the pg_psort.XXX files in my database directory? -3.17) Why can't I connect to my database from another machine? -3.18) How do I find out what indexes or operations are defined in the -database? -3.19) What is the time-warp feature and how does it relate to vacuum? -3.20) What is an oid? What is a tid? -3.21) What is the meaning of some of the terms used in Postgres? -3.22) What is Genetic Query Optimization? -3.23) How do you remove a column from a table? -3.24) How do SELECT only the first few rows of a query? -3.25) Why can't I create a column named "time"? -3.26) How much database disk space is required to store data from a typical -flat file? - -4) Questions about extending PostgreSQL - -4.1) I wrote a user-defined function and when I run it in psql, it dumps -core. -4.2) I get messages of the type NOTICE:PortalHeapMemoryFree: 0x402251d0 -4.3) I've written some nifty new types and functions for PostgreSQL. -4.4) How do I write a C function to return a tuple? - -5) Bugs - -5.1) How do I make a bug report? - - ------------------------------------------------------------------------ - -Section 1: General Questions - -1.1) What is PostgreSQL? - -PostgreSQL is an enhancement of the POSTGRES database management system, a -next-generation DBMS research prototype. While PostgreSQL retains the +

+

Section 1: General Questions

1.1) What is PostgreSQL?

+

+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. - -PostgreSQL development is being performed by a team of Internet developers -who all subscribe to the PostgreSQL development mailing list. The current -coordinator is Marc G. Fournier (scrappy@postgreSQL.org). (See below on how -to join). This team is now responsible for all current and future -development of PostgreSQL. - -The authors of PostgreSQL 1.01 were Andrew Yu and Jolly Chen. Many others -have contributed to the porting, testing, debugging and enhancement of the -code. The original Postgres code, from which PostgreSQL is derived, was the -effort of many graduate students, undergraduate students, and staff -programmers working under the direction of Professor Michael Stonebraker at -the University of California, Berkeley. - -The original name of the software at Berkeley was Postgres. When SQL +PostQuel query language with an extended subset of SQL. PostgreSQL is +free and the complete source is available. +

+PostgreSQL development is being performed by a team of Internet +developers who all subscribe to the PostgreSQL development mailing list. +The current coordinator is Marc G. Fournier (scrappy@postgreSQL.org). (See +below on how to join). This team is now responsible for all current and +future development of PostgreSQL. +

+The authors of PostgreSQL 1.01 were Andrew Yu and Jolly Chen. Many +others have contributed to the porting, testing, debugging and +enhancement of the code. The original Postgres code, from which +PostgreSQL is derived, was the effort of many graduate students, +undergraduate students, and staff programmers working under the +direction of Professor Michael Stonebraker at the University of +California, Berkeley. +

+The original name of the software at Berkeley was Postgres. When SQL functionality was added in 1995, its name was changed to Postgres95. The name was changed at the end of 1996 to PostgreSQL. - -1.2) What does PostgreSQL run on? - +

+

1.2) What does PostgreSQL run +on?

+

The authors have compiled and tested PostgreSQL on the following platforms(some of these compiles require gcc 2.7.0): - - * aix - IBM on AIX 3.2.5 or 4.x - * alpha - DEC Alpha AXP on Digital Unix 2.0, 3.2, 4.0 - * BSD44_derived - OSs derived from 4.4-lite BSD (NetBSD, FreeBSD) - * bsdi - BSD/OS 2.0, 2.01, 2.1, 3.0 - * dgux - DG/UX 5.4R4.11 - * hpux - HP PA-RISC on HP-UX 9.0, 10 - * i386_solaris - i386 Solaris - * irix5 - SGI MIPS on IRIX 5.3 - * linux - Intel x86 on Linux 2.0 and Linux ELF SPARC on Linux ELF PPC on - Linux Elf (For non-ELF Linux, see LINUX_ELF below). - * sco - SCO 3.2v5 - * sparc_solaris - SUN SPARC on Solaris 2.4, 2.5, 2.5.1 - * sunos4 - SUN SPARC on SunOS 4.1.3 - * svr4 - Intel x86 on Intel SVR4 and MIPS - * ultrix4 - DEC MIPS on Ultrix 4.4 - +

The following platforms have known problems/bugs: - - * nextstep - Motorola MC68K or Intel x86 on NeXTSTEP 3.2 - -1.3) Where can I get PostgreSQL? - -The primary anonymous ftp site for PostgreSQL is: - - * ftp://ftp.postgreSQL.org/pub - -A mirror site exists at: - - * ftp://postgres95.vnet.net/pub/postgres95 - * ftp://ftp.luga.or.at/pub/postgres95 - * ftp://cal011111.student.utwente.nl/pub/postgres95 - * ftp://ftp.uni-trier.de/pub/database/rdbms/postgres/postgres95 - * ftp://rocker.sch.bme.hu - -1.4) What's the copyright on PostgreSQL? - + +

+

1.3) Where can I get PostgreSQL?

+

The primary anonymous ftp site for PostgreSQL is: +

+

A mirror site exists at: +

+

1.4) What's the copyright on +PostgreSQL?

+

PostgreSQL is subject to the following COPYRIGHT. - +

PostgreSQL Data Base Management System - +

Copyright (c) 1994-6 Regents of the University of California - +

Permission to use, copy, modify, and distribute this software and its -documentation for any purpose, without fee, and without a written agreement -is hereby granted, provided that the above copyright notice and this -paragraph and the following two paragraphs appear in all copies. - -IN NO EVENT SHALL THE UNIVERSITY OF CALIFORNIA BE LIABLE TO ANY PARTY FOR -DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES, INCLUDING -LOST PROFITS, ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, -EVEN IF THE UNIVERSITY OF CALIFORNIA HAS BEEN ADVISED OF THE POSSIBILITY OF -SUCH DAMAGE. - +documentation for any purpose, without fee, and without a written +agreement is hereby granted, provided that the above copyright notice +and this paragraph and the following two paragraphs appear in all +copies. +

+IN NO EVENT SHALL THE UNIVERSITY OF CALIFORNIA BE LIABLE TO ANY PARTY +FOR DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES, +INCLUDING LOST PROFITS, ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS +DOCUMENTATION, EVEN IF THE UNIVERSITY OF CALIFORNIA HAS BEEN ADVISED OF +THE POSSIBILITY OF SUCH DAMAGE. +

THE UNIVERSITY OF CALIFORNIA SPECIFICALLY DISCLAIMS ANY WARRANTIES, -INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND -FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS ON AN -"AS IS" BASIS, AND THE UNIVERSITY OF CALIFORNIA HAS NO OBLIGATIONS TO -PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS. - -1.5) Support for PostgreSQL - -There is no official support for PostgreSQL from the original maintainers or -from University of California, Berkeley. It is maintained through volunteer -effort only. - -The main mailing list is: questions@postgreSQL.org. It is available for -discussion o f matters pertaining to PostgreSQL, including but not limited -to bug reports and fixes. For info on how to subscribe, send a mail with the -lines in the body (not the subject line) - +INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY +AND FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER +IS ON AN "AS IS" BASIS, AND THE UNIVERSITY OF CALIFORNIA HAS NO +OBLIGATIONS TO PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR +MODIFICATIONS. +

+

1.5) Support for PostgreSQL

+

+There is no official support for PostgreSQL from the original +maintainers or from University of California, Berkeley. It is +maintained through volunteer effort only. +

+The main mailing list is: questions@postgreSQL.org. It +is available for discussion o f matters pertaining to PostgreSQL, +including but not limited to bug reports and fixes. For info on how to +subscribe, send a mail with the lines in the body (not the subject line) +

+
         subscribe
         end
-
-to questions-request@postgreSQL.org.
-
-There is also a digest list available. To subscribe to this list, send email
-to: questions-digest-request@postgreSQL.org with a BODY of:
-
+
+
+

+to questions-request@postgreSQL.org +. +

+There is also a digest list available. To subscribe to this list, send +email to: + +questions-digest-request@postgreSQL.org with a BODY of: +

+
         subscribe
         end
-
+
+
Digests are sent out to members of this list whenever the main list has received around 30k of messages. - -There is a bugs mailing list available. To subscribe to this list, send -email to bugs-request@postgreSQL.org with a BODY of: - -There is also a developers discussion mailing list available. To subscribe -to this list, send email to hackers-request@postgreSQL.org with a BODY of: - +

+There is a bugs mailing list available. To subscribe to this +list, send email to bugs-request@postgreSQL.org +with a BODY of: +

+There is also a developers discussion mailing list available. To subscribe to +this +list, send email to hackers-request@postgreSQL.org +with a BODY of: +

+

+
         subscribe
         end
-
-Additional information about PostgreSQL can be found via the PostgreSQL WWW
-home page at:
-
-     http://postgreSQL.org
-
-1.6) Latest release of PostgreSQL
-
+
+
+

+Additional information about PostgreSQL can be found via the PostgreSQL +WWW home page at: +

+ http://postgreSQL.org +
+

+

1.6) Latest release of PostgreSQL

+

The latest release of PostgreSQL is version 6.2.1, which was released on -October 17th, 1997. We are testing 6.3 beta. For information about what is -new in 6.3, see our TODO list on our WWW page. - +October 17th, 1997. We are testing 6.3 beta. For information about +what is new in 6.3, see our TODO list on our WWW page. +

We plan to have major releases every three months. - -1.7) Is there a commercial version of PostgreSQL? - +

+

1.7) Is there a commercial version of PostgreSQL? +

Illustra Information Technology (a wholly owned subsidiary of Informix Software, Inc.) sells an object-relational DBMS called Illustra that was originally based on postgres. Illustra has cosmetic similarities to PostgreSQL but has more features, is more robust, performs better, and -offers real documentation and support. On the flip side, it costs money. For -more information, contact sales@illustra.com - -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 +offers real documentation and support. On the flip side, it costs +money. For more information, contact sales@illustra.com +

+

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. - -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 support for nested subqueries - * no HAVING clause under a GROUP BY - +

+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: +

+

On the other hand, you get to create user-defined types, functions, -inheritance etc. If you're willing to help with PostgreSQL coding, -eventually we can also add the missing features listed above. - -1.10) Does PostgreSQL work with databases from earlier versions of postgres? - +inheritance etc. +

+

1.10) Does PostgreSQL work with databases from +earlier versions of postgres?

+

PostgreSQL v1.09 is compatible with databases created with v1.01. - +

Upgrading to 6.3 from earlier releases requires a dump and restore. - +

Upgrading to 6.2.1 from pre-6.2 requires a dump and restore. - -Upgrading to 6.2.1 from 6.2 does not require a dump, but see the appropriate -/migration file in the distribution. - -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. - -1.11) Are there ODBC drivers for PostgreSQL? - +

+Upgrading to 6.2.1 from 6.2 does not require a dump, but see the +appropriate /migration file in the distribution. +

+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. +

+

1.11) Are there ODBC drivers for PostgreSQL?

+

There are two ODBC drivers available, PostODBC and OpenLink ODBC. - -For all people being interested in PostODBC, there are now two mailing lists -devoted to the discussion of PostODBC. The mailing lists are: - - * postodbc-users@listserv.direct. net - * postodbc-developers@listse rv.direct.net - -these lists are ordinary majordomo mailing lists. You can subscribe by +

+PostODBC is included in the distribution. +For all people being interested in PostODBC, there are now two mailing +lists devoted to the discussion of PostODBC. The mailing lists are: +

+

+these lists are ordinary majordomo mailing lists. You can subscribe by sending a mail to: - - * 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 Postgres ODBC available on every client -platform we support (Win, Mac, Unix, VMS). - +

+

+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 Postgres 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 available. -Questions to postgres95@openlink.co.uk. - -1.12) What tools are available for hooking postgres to Web pages? - +commercial-quality support, but a freeware version will always be +available. Questions to postgres95@openlink.co.uk. +

+

1.12) What tools are available for hooking +postgres to Web pages?

+

A nice introduction to Database-backed Web pages can be seen at: -http://www.webtools.com - -For web integration, PHP is an excellent interface. The URL for that is -http://php.iquest.net - -PHP is great for simple stuff, but for more complex stuff, some still use -the perl interface and CGI.pm. - +http://www.webtools.com +

+For web integration, PHP is an excellent interface. The URL for that +is http://www.php.net +

+PHP is great for simple stuff, but for more complex stuff, some still +use the perl interface and CGI.pm. +

An WWW gatway based on WDB using perl can be downloaded from: +

+

1.13) Does PostgreSQL have a graphical user interface +? +A report generator? A embedded query language interface?

+

+We have a nice graphical user interface called pgaccess, which is +shipped as part of the distribtion. Pgaccess also has a report +generator. +

+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?

+

+Many of our users like The Practical SQL Handbook, +Bowman et al, Addison Wesley. +

- * http://www.eol.ists.ca/~dunlop/wdb -p95 - -1.13) Does PostgreSQL have a graphical user interface? A report generator? A -embedded query language interface? - -No. No. No. Not in the official distribution at least. Some users have -reported some success at using 'pgbrowse' and 'onyx' as frontends to -PostgreSQL. Several contributions are working on tk based frontend tools. -Ask on the mailing list. - -1.14) What is a good book to learn SQL? - -Many of our users like The Practical SQL Handbook, Bowman et al, Addison -Wesley. - - ------------------------------------------------------------------------ - -Section 2: Installation Questions - -2.1) initdb doesn't run - - * check to see that you have the proper paths set - * check that the 'postgres' user owns all the right files - * ensure that there are files in $PGDATA/files, and that they are - non-empty. If they aren't, then "gmake install" failed for some reason - -2.2) when I start up the postmaster, I get "FindBackend: could not find a -backend to execute..." "postmaster: could not find backend to execute..." - -You probably do not have the right path set up. The 'postgres' executable -needs to be in your path. - -2.3) The system seems to be confused about commas, decimal points, and date -formats. - -Check your locale configuration. PostgreSQL uses the locale settings of the -user that ran the postmaster process. Set those accordingly for your -operating environment. - -2.4) How do I install PostgreSQL somewhere other than /usr/local/pgsql? - +

+

Section 2: Installation Questions +

+

+

2.1) initdb doesn't run

+

+

+

+

2.2) when I start up the postmaster, I get + "FindBackend: could not find a backend to execute..." + "postmaster: could not find backend to execute..."

+

+You probably do not have the right path set up. The 'postgres' +executable needs to be in your path. +

+

2.3) The system seems to be confused about commas, +decimal points, and date formats.

+

+Check your locale configuration. PostgreSQL uses the locale settings of +the user that ran the postmaster process. Set those accordingly for +your operating environment. +

+

2.4) How do I install PostgreSQL somewhere other tha +n +/usr/local/pgsql?

+

You need to edit Makefile.global and change POSTGRESDIR accordingly, or create a Makefile.custom and define POSTGRESDIR there. - -2.5) When I run postmaster, I get a Bad System Call core dumped message. - +

+

2.5) When I run postmaster, I get a Bad System +Call core dumped message.

+

It could be a variety of problems, but first check to see that you have system V extensions installed on your kernel. PostgreSQL requires kernel support for shared memory. - -2.6) When I try to start the postmaster, I get IpcMemoryCreate errors. - -You either do not have shared memory configured properly in kernel or you -need to enlarge the shared memory available in the kernel. The exact amount -you need depends on your architecture and how many buffers you configure -postmaster to run with. For most systems, with default buffer sizes, you -need a minimum of ~760K. - -2.7) I have changed a source file, but a recompile does not see the change? - +

+

2.6) When I try to start the postmaster, I get +IpcMemoryCreate errors.

+

+You either do not have shared memory configured properly in kernel or +you need to enlarge the shared memory available in the kernel. The +exact amount you need depends on your architecture and how many buffers +you configure postmaster to run with. For most systems, with default +buffer sizes, you need a minimum of ~760K. +

+

2.7) I have changed a source file, but a +recompile does not see the change?

+

The Makefiles do not have the proper dependencies for include files. You have to do a 'make clean' and then another 'make'. - -2.8) How do I prevent other hosts from accessing my PostgreSQL backend? - -Use host-based authentication by modifying the file $PGDATA/pg_hba +

+

2.8) How do I prevent other hosts from accessing my +PostgreSQL backend?

+

+By default, PostgreSQL only allows connections from the local machine +using unix domain. You must add the -i flag to the postmaster, and +enable host-based authentication by modifying the file $PGDATA/pg_hba accordingly. - -2.9) I can't access the database as the 'root' user. - -You should not create database users with user id 0(root). They will be -unable to access the database. This is a security precaution because of the -ability of any user to dynamically link object modules into the database -engine. - -2.10) All my servers crash under concurrent table access. Why? - +

+

2.9) I can't access the database as the 'root' +user.

+

+You should not create database users with user id 0(root). They will be +unable to access the database. This is a security precaution because +of the ability of any user to dynamically link object modules into the +database engine. +

+

2.10) All my servers crash under concurrent table +access. Why?

+

This problem can be caused by a kernel that is not configured to support semaphores. - -2.11) How do I tune the database engine for better performance? - -There are two things that can be done. You can use Openlink's option to -disable fsync() by starting the postmaster with a '-o -F' option. This will -prevent fsync()'s from flushing to disk after every transaction. - -You can also use the postmaster -B option to increase the number of shared -memory buffers shared among the backend processes. If you make this -parameter too high, the process will not start or crash unexpectedly. Each -buffer is 8K and the defualt is 64 buffers. - -You can also use the postgres -S option to increase the maximum amount of -memory used by each backend process for temporary sorts. Each buffer is 1K -and the defualt is 512 buffers. - -2.12) What debugging features are available in PostgreSQL? - -PostgreSQL has several features that report status information that can be -valuable for debugging purposes. - -First, by running configure with the -enable-cassert option, many assert()'s -monitor the progress of the backend and halt the program when something -unexpected occurs. - -Both postmaster and postgres have several debug options available. First, -whenever you start the postmaster, make sure you send the standard output -and error to a log file, like: - +

+

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 +starting the postmaster with a '-o -F' option. This +will prevent fsync()'s from flushing to disk after every transaction. +

+You can also use the postmaster -B option to increase the number of +shared memory buffers shared among the backend processes. If you make +this parameter too high, the process will not start or crash +unexpectedly. Each buffer is 8K and the defualt is 64 buffers. +

+You can also use the postgres -S option to increase the maximum +amount of memory used by each backend process for temporary sorts. +Each buffer is 1K and the defualt is 512 buffers. +

+

2.12) What debugging features are available in +PostgreSQL?

+

+PostgreSQL has several features that report status information that can +be valuable for debugging purposes. +

+First, by running configure with the -enable-cassert option, +many assert()'s monitor the progress of the backend and halt the +program when something unexpected occurs. +

+Both postmaster and postgres have several debug options available. +First, whenever you start the postmaster, make sure you send the +standard output and error to a log file, like: +

+
         cd /usr/local/pgsql
-        ./bin/postmaster >server.log 2>&1 &
-
-This will put a server.log file in the top-level PostgreSQL directory. This
-file can contain useful information about problems or errors encountered by
-the server. Postmaster has a -d option that allows even more detailed
-information to be reported. The -d option takes a number 1-3 that specifies
-the debug level. Be warned that a debug level of 3 generates large log
-files.
-
+        ./bin/postmaster >server.log 2>&1 &
+
+
+

+This will put a server.log file in the top-level PostgreSQL directory. +This file can contain useful information about problems or errors +encountered by the server. Postmaster has a -d option that allows even +more detailed information to be reported. The -d option takes a number +1-3 that specifies the debug level. Be warned that a debug level +of 3 generates large log files. +

You can actuall run the postgres backend from the command line, and type -your SQL statement directly. This is recommended ONLY for debugging -purposes. Note that a newline terminates the query, not a semicolon. If you -have compiled with debugging symbols, you can use a debugger to see what is -happening. Because the backend was not started from the postmaster, it is -not running in an identical environment and locking/backend interaction -problems may not be duplicated. Some operating system can attach to a -running backend directly to diagnose problems. - -The postgres program has a -s, -A, -t options that can be very usefull for -debugging and performance measurements. - +your SQL statement directly. This is recommended ONLY for debugging +purposes. Note that a newline terminates the query, not a semicolon. If +you have compiled with debugging symbols, you can use a debugger +to see what is happening. Because the backend was not started from the +postmaster, it is not running in an identical environment and +locking/backend interaction problems may not be duplicated. Some +operating system can attach to a running backend directly to diagnose +problems. +

+The postgres program has a -s, -A, -t options that can be very usefull +for debugging and performance measurements. +

You can also compile with profiling to see what functions are taking -execution time. The backend profile files will be deposited in the -pgsql/data/base/dbname directory. The client profile file will be put in the -current directory. - +execution time. The backend profile files will be deposited in the +pgsql/data/base/dbname directory. The client profile file will be put +in the current directory. +

The EXPLAIN command (see this FAQ) allows you to see how PostgreSQL is interpreting your query. +

+

2.13) How do I enable more than 32 concurrent +backends?

+

+Edit include/storage/sinvaladt.h, and change the value of MaxBackendId. +In the future, we plan to make this a configurable prameter. +

-2.13) How do I enable more than 32 concurrent backends? - -Edit include/storage/sinvaladt.h, and change the value of MaxBackendId. In -the future, we plan to make this a configurable prameter. - - ------------------------------------------------------------------------ - -Section 3: PostgreSQL Features - -3.1) Does PostgreSQL support nested subqueries? - -Subqueries are not implemented, but they can be simulated using sql -functions. - -3.2) I've having a lot of problems using rules. - -Currently, the rule system in PostgreSQL is mostly broken. It works enough -to support the view mechanism, but that's about it. Use PostgreSQL rules at -your own peril. - -3.3) I can't seem to write into the middle of large objects reliably. - -The Inversion large object system in PostgreSQL is also mostly broken. It -works well enough for storing large wads of data and reading them back out, -but the implementation has some underlying problems. Use PostgreSQL large -objects at your own peril. - -3.4) How can I write client applications to PostgreSQL? - -PostgreSQL supports a C-callable library interface called libpq as well as -many others. See the /src/interfaces directory. - -Others have contributed a perl interface and a WWW gateway to PostgreSQL. -See the PostgreSQL home pages for more details. - -3.5) How do I set up a pg_group? - +

+

Section 3: PostgreSQL Features +

+

+

3.1) Does PostgreSQL support nested subqueries?

+

+Yes. +

+

3.2) I've having a lot of problems using rules.

+

+Currently, the rule system in PostgreSQL has some limitations. It works +enough to support the view mechanism, but does not handle +Insert/Update/Delete well. +

+

3.3) I can't seem to write into the middle of large +objects reliably.

+

+The Inversion large object system now works perfectly. You should no +longer have problems with large objects. +

+

3.4) How can I write client applications to PostgreS +QL?

+

+PostgreSQL supports a C-callable library interface called libpq as well +as many others. See the /src/interfaces directory. +

+Others have contributed a perl interface and a WWW gateway to +PostgreSQL. See the PostgreSQL home pages for more details. +

+

3.5) How do I set up a pg_group?

+

Currently, there is no easy interface to set up user groups. You have to explicitly insert/update the pg_group table. For example: - - jolly=> insert into pg_group (groname, grosysid, grolist) - jolly=> values ('posthackers', '1234', '{5443, 8261}'); +

+
+        jolly=> insert into pg_group (groname, grosysid, grolist)
+        jolly=>     values ('posthackers', '1234', '{5443, 8261}');
         INSERT 548224
-        jolly=> grant insert on foo to group posthackers;
+        jolly=> grant insert on foo to group posthackers;
         CHANGE
-        jolly=>
-
-The fields in pg_group are:
-
-   * groname: the group name. This a char16 and should be purely
-     alphanumeric. Do not include underscores or other punctuation.
-   * grosysid: the group id. This is an int4. This should be unique for each
-     group.
-   * grolist: the list of pg_user id's that belong in the group. This is an
-     int4[].
-
-3.6) What is the exact difference between binary cursors and normal cursors?
-
-See the declare manual page for a description.
-
-3.7) What is a R-tree index and what is it used for?
-
-An r-tree index is used for indexing spatial data. A hash index can't handle
-range searches. A B-tree index only handles range searches in a single
-dimension. R-tree's can handle multi-dimensional data. For example, if a
-R-tree index can be built on an attribute of type 'point', the system can
-more efficient answer queries like select all points within a bounding
-rectangle.
-
+        jolly=>
+
+
+

+ The fields in pg_group are: +

+

+

3.6) What is the exact difference between binary +cursors and normal cursors?

+

+See the declare manual page for a description. +

+

3.7) What is a R-tree index and what is it used for? +

+

+An r-tree index is used for indexing spatial data. A hash index can't +handle range searches. A B-tree index only handles range searches in a +single dimension. R-tree's can handle multi-dimensional data. For +example, if a R-tree index can be built on an attribute of type 'point', +the system can more efficient answer queries like select all points +within a bounding rectangle. +

The canonical paper that describes the original R-Tree design is: - -Guttman, A. "R-Trees: A Dynamic Index Structure for Spatial Searching." Proc -of the 1984 ACM SIGMOD Int'l Conf on Mgmt of Data, 45-57. - -You can also find this paper in Stonebraker's "Readings in Database Systems" - -Builtin R-Trees can handle polygons and boxes. In theory, R-trees can be -extended to handle higher number of dimensions. In practice, extending -R-trees require a bit of work and we don't currently have any documentation -on how to do it. - -3.8) What is the maximum size for a tuple? - -Tuples are limited to 8K bytes. Taking into account system attributes and -other overhead, one should stay well shy of 8,000 bytes to be on the safe -side. To use attributes larger than 8K, try using the large objects -interface. - -Tuples do not cross 8k boundaries so a 5k tuple will require 8k of storage. - -3.9) I defined indices but my queries don't seem to make use of them. Why? - -PostgreSQL does not automatically maintain statistics. One has to make an -explicit 'vacuum' call to update the statistics. After statistics are -updated, the optimizer has a better shot at using indices. Note that the -optimizer is limited and does not use indices in some circumstances (such as -OR clauses). For column-specific optimization statistics, use 'vacuum -analyze'. - -If the system still does not see the index, it is probably because you have -created an index on a field with the improper *_ops type. For example, you -have created a CHAR(4) field, but have specified a char_ops index -type_class. - -See the create_index manual page for information on what type classes are -available. It must match the field type. - +

+Guttman, A. "R-Trees: A Dynamic Index Structure for Spatial Searching." +Proc of the 1984 ACM SIGMOD Int'l Conf on Mgmt of Data, 45-57. +

+You can also find this paper in Stonebraker's "Readings in Database +Systems" +

+Builtin R-Trees can handle polygons and boxes. In theory, R-trees can +be extended to handle higher number of dimensions. In practice, +extending R-trees require a bit of work and we don't currently have any +documentation on how to do it. +

+

3.8) What is the maximum size for a tuple?

+

+Tuples are limited to 8K bytes. Taking into account system attributes +and other overhead, one should stay well shy of 8,000 bytes to be on the +safe side. To use attributes larger than 8K, try using the large +objects interface. +

+Tuples do not cross 8k boundaries so a 5k tuple will require 8k of +storage. +

+

3.9) I defined indices but my queries don't seem +to make use of them. Why?

+

+PostgreSQL does not automatically maintain statistics. One has to make +an explicit 'vacuum' call to update the statistics. After statistics +are updated, the optimizer has a better shot at using indices. Note +that the optimizer is limited and does not use indices in some +circumstances (such as OR clauses). For column-specific optimization +statistics, use 'vacuum analyze'. +

+If the system still does not see the index, it is probably because you +have created an index on a field with the improper *_ops type. For +example, you have created a CHAR(4) field, but have specified a char_ops +index type_class. +

+See the create_index manual page for information on what type classes +are available. It must match the field type. +

Postgres does not warn the user when the improper index is created. - +

Indexes not used for ORDER BY operations. - -3.10) How do I do regular expression searches? case-insensitive regexp -searching? - -See the pgbuiltin manual page. Search for regular expression. - -3.11) I experienced a server crash during a vacuum. How do I remove the lock -file? - -See the vacuum manual page. - -3.12) What is the difference between the various character types? - +

+

3.10) How do I do regular expression searches? +case-insensitive regexp searching?

+

+See the pgbuiltin manual page. Search for regular expression. +

+

3.11) I experienced a server crash during a +vacuum. How do I remove the lock file?

+

+See the vacuum manual page. +

+

3.12) What is the difference between the various +character types?

+
 Type            Internal Name   Notes
 --------------------------------------------------
 CHAR            char            1 character   }
@@ -593,180 +723,185 @@ CHAR(#)         bpchar          blank padded to the specified fixed length
 VARCHAR(#)      varchar         size specifies maximum length, no padding
 TEXT            text            length limited only by maximum tuple length
 BYTEA           bytea           variable-length array of bytes
-
+
+

You need to use the internal name when doing internal operations. - -The last four types above are "varlena" types (i.e. the first four bytes are -the length, followed by the data). CHAR(#) allocates the maximum number of -bytes no matter how much data is stored in the field. TEXT, VARCHAR(#), and -BYTEA all have variable length on the disk, and because of this, there is a -small performance penalty for using them. Specifically, the penalty is for -access to any columns after the first column of this type. - -3.13) In a query, how do I detect if a field is NULL? - +

+The last four types above are "varlena" types (i.e. the first four bytes +are the length, followed by the data). CHAR(#) allocates the maximum +number of bytes no matter how much data is stored in the field. +TEXT, VARCHAR(#), and BYTEA all have variable length on the disk, and +because of this, there is a small performance penalty for using them. +Specifically, the penalty is for access to any columns after the first +column of this type. +

+

3.13) In a query, how do I detect if a field is NULL? +

+

You test the column with IS NULL and IS NOT NULL. - -3.14) How do I see how the query optimizer is evaluating my query? - -See the explain manual page. - -3.15) How do I create a serial field? - -Postgres does not allow the user to specifiy a user column as type SERIAL. -Instead, you can use each row's oid field as a unique value. However, if you -need to dump and reload the database, you need to use pgdump's -o option or -COPY's WITH OIDS option to preserver the oids. - -We also have a SEQUENCE function that is similar to SERIAL. See the +

+

3.14) How do I see how the query optimizer is +evaluating my query?

+

+See the explain manual page. +

+

3.15) How do I create a serial field?

+

+Postgres does not allow the user to specifiy a user column as type +SERIAL. Instead, you can use each row's oid field as a unique value. +However, if you need to dump and reload the database, you need to use +pgdump's -o option or COPY's WITH OIDS option to preserver the oids. +

+We also have a SEQUENCE function that is similar to SERIAL. See the create_sequence manual page. - +

Another valid way of doing this is to create a function: - +

+
         create table my_oids (f1 int4);
         insert into my_oids values (1);
         create function new_oid () returns int4 as
                 'update my_oids set f1 = f1 + 1;  select f1 from my_oids; '
         language 'sql';
-
+
+
+

then: - +

+
         create table my_stuff (my_key int4, value text);
         insert into my_stuff values (new_oid(), 'hello');
-
-However, keep in mind there is a race condition here where one server could
-do the update, then another one do an update, and they both could select the
-same new id. This statement should be performed within a transaction.
-
-Yet another way is to use general trigger function autoinc() from
-contrib/spi/autoinc.c.
-
-3.16) What are the pg_psort.XXX files in my database directory?
-
-They are temporary sort files generated by the query executor. For example,
-if a sort needs to be done to satisfy an ORDER BY, some temp files are
-generated as a result of the sort.
-
+
+
+

+However, keep in mind there is a race condition here where one server +could do the update, then another one do an update, and they both could +select the same new id. This statement should be performed within a +transaction. +

+Yet another way is to use general trigger function autoinc() +from contrib/spi/autoinc.c. +

+

3.16) What are the pg_psort.XXX files in my database +directory?

+

+They are temporary sort files generated by the query executor. +For example, if a sort needs to be done to satisfy an ORDER BY, +some temp files are generated as a result of the sort. +

If you have no transactions or sorts running at the time, it is safe to delete the pg_psort.XXX files. - -3.17) Why can't I connect to my database from another machine? - -The default configuration allows only connections from tcp/ip host -localhost. You need to add a host entry to the file pgsql/data/pg_hba. See -the hba_conf manual page. - -3.18) How do I find out what indexes or operations are defined in the -database? - -Run the file pgsql/src/tutorial/syscat.source. It illustrates many of the -'select's needed to get information out of the database system tables. - -3.19) What is the time-warp feature and how does it relate to vacuum? - -PostgreSQL handles data changes differently than most database systems. When -a row is changed in a table, the original row is marked with the time it was -changed, and a new row is created with the current data. By default, only -current rows are used in a table. If you specify a date/time after the table -name in a FROM clause, you can access the data that was current at that -time, i.e. - - SELECT * - FROM employees ['July 24, 1996 09:00:00'] - -displays employee rows in the table at the specified time. You can specify -intervals like [date,date], [date,], [,date], or [,]. This last option -accesses all rows that ever existed. - -INSERTed rows get a timestamp too, so rows that were not in the table at the -desired time will not appear. - -Vacuum removes rows that are no longer current. This time-warp feature is -used by the engine for rollback and crash recovery. Expiration times can be -set with purge. - -In 6.0, once a table is vacuumed, the creation time of a row may be -incorrect, causing time-traval to fail. - -The time-travel feature will be removed in 6.3. - -3.20) What is an oid? What is a tid? - -Oids are Postgres's answer to unique row ids or serial columns. Every row -that is created in Postgres gets a unique oid. All oids generated by initdb -are less than 16384 (from backend/access/transam.h). All post-initdb -(user-created) oids are equal or greater that this. All these oids are -unique not only within a table, or database, but unique within the entire -postgres installation. - -Postgres uses oids in its internal system tables to link rows in separate -tables. These oids can be used to identify specific user rows and used in -joins. It is recommended you use column type oid to store oid values. See -the sql(l) manual page to see the other internal columns. You can create an -index on the oid field for faster access. - +

+

3.17) Why can't I connect to my database from +another machine?

+

+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. +

+

3.18) How do I find out what indexes or +operations are defined in the database?

+

+psql has a variety of backslash commands to show such information. Use +\? to see them. +

+Also try the file pgsql/src/tutorial/syscat.source. It illustrates many of +the 'select's needed to get information out of the database system +tables. +

+

3.19) What is the time-warp feature and how does +it relate to vacuum?

+

+PostgreSQL no longer supports this feature. All support code has been +removed. This was done to improve performance and reduce disk storage +overhead. +

+

3.20) What is an oid? What is a tid?

+

+Oids are Postgres's answer to unique row ids or serial columns. Every +row that is created in Postgres gets a unique oid. All oids generated +by initdb are less than 16384 (from backend/access/transam.h). All +post-initdb (user-created) oids are equal or greater that this. All +these oids are unique not only within a table, or database, but unique +within the entire postgres installation. +

+Postgres uses oids in its internal system tables to link rows in +separate tables. These oids can be used to identify specific user rows +and used in joins. It is recommended you use column type oid to store +oid values. See the sql(l) manual page to see the other internal +columns. You can create an index on the oid field for faster access. +

Tids are used to indentify specific physical rows with block and offset -values. Tids change after rows are modified or reloaded. They are used by -index entries to point to physical rows. They can not be accessed through -sql. - -3.21) What is the meaning of some of the terms used in Postgres? - +values. Tids change after rows are modified or reloaded. They are used +by index entries to point to physical rows. They can not be accessed +through sql. +

+

3.21) What is the meaning of some of the terms +used in Postgres?

+

Some of the source code and older documentation use terms that have more -common usage. Here are some: - - * row, record, tuple - * attribute, field, column - * table, class - * retrieve, select - * replace, update - * append, insert - * oid, serial value - * portal, cursor - * range variable, table name, table alias - +common usage. Here are some: +

+

Please let me know if you think of any more. - -3.22) What is Genetic Query Optimization? - -The GEQO module in PostgreSQL is intended to solve the query optimization -problem of joining many tables by means of a Genetic Algorithm (GA). It -allows the handling of large join queries through non-exhaustive search. - -For further information see README.GEQO . - -3.23) How do you remove a column from a table? - +

+

3.22) What is Genetic Query Optimization?

+

+The GEQO module in PostgreSQL is intended to solve the query +optimization problem of joining many tables by means of a Genetic +Algorithm (GA). It allows the handling of large join queries through +non-exhaustive search. +

+For further information see README.GEQO <utesch@aut.tu-freiberg.de>. +

+

3.23) How do you remove a column from a table?

We do not support ALTER TABLE DROP COLUMN, but do this: - +
+
         SELECT ...  -- select all columns but the one you want to remove
         INTO TABLE new_table
         FROM old_table;
         DROP TABLE old_table;
         ALTER TABLE new_table RENAME TO old_table;
-
-3.24) How do SELECT only the first few rows of a query?
-
-See the fetch manual page.
-
-This only prevents all row results from being transfered to the client. The
-entire query must be evaluated, even if you only want just first few rows.
-Consider a query that has and ORDER BY. There is no way to return any rows
-until the entire query is evaluated and sorted.
-
-3.25) Why can't I create a column named "time"?
-
+
+
+

+

3.24) How do SELECT only the first few rows of +a query?

+

+See the fetch manual page. +

+This only prevents all row results from being transfered to the client. +The entire query must be evaluated, even if you only want just first few +rows. +Consider a query that has and ORDER BY. There is no way to return any +rows until the entire query is evaluated and sorted. +

+

3.25) Why can't I create a column named +"time"?

+

6.2.1 has added some new restricted keywords as we make PostgreSQL more -ANSI-92 compilant. The next release will have this restriction removed. +ANSI-92 compilant. The next release will have this restriction removed. There is a patch on ftp.postgresql.org that will allow this feature now. - -3.26)How much database disk space is required to store data from a typical -flat file? - -Consider a file with 300,000 lines with two integers on each line. The flat -file is 2.4MB. The size of the PostgreSQL database file containing this data -can be estimated: - +

+

3.26)How much database disk space is required +to store data from a typical flat file?

+

+Consider a file with 300,000 lines with two integers on each line. +The flat file is 2.4MB. The size of the PostgreSQL database file +containing this data can be estimated: +

 40 bytes + each row header (approximate)
  8 bytes + two int fields @ 4 bytes each
  4 bytes + pointer on page to tuple
@@ -784,54 +919,67 @@ The data page size in PostgreSQL is 8192(8k) bytes, so:
 157 rows per page
 
 1911 database pages * 8192 bytes per page  =  15,654,912 or 15.5MB
-
+

 Indexes do not contain as much overhead, but do contain the data that
 is being indexed, so they can be large also.
+
+

+

+

Section 4: Extending PostgreSQL +

+

+

4.1) I wrote a user-defined function and when I run +it +in psql, it dumps core.

+

+The problem could be a number of things. Try testing your user-defined +function in a stand alone test program first. Also, make sure you are +not sending elog NOTICES when the front-end is expecting data, such as +during a type_in() or type_out() functions +

+

4.2) I get messages of the type + NOTICE:PortalHeapMemoryFree: 0x402251d0 not in alloc set!

+

+You are pfree'ing something that was not palloc'ed. When writing +user-defined functions, do not include the file "libpq-fe.h". Doing so +will cause your palloc to be a malloc instead of a free. Then, when the +backend pfrees the storage, you get the notice message. +

+

4.3) I've written some nifty new types and functions + for +PostgreSQL.

+

+Please share them with other PostgreSQL users. Send your extensions to +mailing list, and they will eventually end up in the contrib/ +subdirectory. +

+

4.4) How do I write a C function to return a tuple?< +/H3> +

+This requires extreme wizardry, so extreme that the authors have not +ever tried it, though in principle it can be done. The short answer is +... you can't. This capability is forthcoming in the future. +

- ------------------------------------------------------------------------ - -Section 4: Extending PostgreSQL - -4.1) I wrote a user-defined function and when I run it in psql, it dumps -core. - -The problem could be a number of things. Try testing your user-defined -function in a stand alone test program first. Also, make sure you are not -sending elog NOTICES when the front-end is expecting data, such as during a -type_in() or type_out() functions - -4.2) I get messages of the type NOTICE:PortalHeapMemoryFree: 0x402251d0 not -in alloc set! - -You are pfree'ing something that was not palloc'ed. When writing -user-defined functions, do not include the file "libpq-fe.h". Doing so will -cause your palloc to be a malloc instead of a free. Then, when the backend -pfrees the storage, you get the notice message. - -4.3) I've written some nifty new types and functions for PostgreSQL. - -Please share them with other PostgreSQL users. Send your extensions to -mailing list, and they will eventually end up in the contrib/ subdirectory. - -4.4) How do I write a C function to return a tuple? - -This requires extreme wizardry, so extreme that the authors have not ever -tried it, though in principle it can be done. The short answer is ... you -can't. This capability is forthcoming in the future. - - ------------------------------------------------------------------------ - -Section 5: Bugs - -5.1) How do I make a bug report? - -Check the current FAQ at http://postgreSQL.org - -Also check out our ftp site ftp://ftp.postgreSQL.org/pub to see if there is -a more recent PostgreSQL version. - +

+

Section 5: Bugs +

+

+

5.1) How do I make a bug report?

+

+Check the current FAQ at http://postgreSQL.org +

+Also check out our ftp site ftp://ftp.postgreSQL.org/pub to +see if there is a more recent PostgreSQL version. +

You can also fill out the "bug-template" file and send it to: - - * bugs@postgreSQL.org - +

+

This is the address of the developers mailing list. + + + diff --git a/doc/TODO b/doc/TODO index e68b28aceb..3df2d583ad 100644 --- a/doc/TODO +++ b/doc/TODO @@ -1,8 +1,8 @@ TODO list for PostgreSQL ======================== -Last updated: Sun Feb 1 15:08:57 EST 1998 +Last updated: Fri Feb 27 13:32:53 EST 1998 -Current maintainer: Bruce Momjian (maillist@candle.pha.pa.us) +Current maintainer: Bruce Momjian (maillist@candle.pha.pa.us) The most recent version of this document can be viewed at the PostgreSQL WWW site, http://www.postgreSQL.org. @@ -13,49 +13,50 @@ A dash(-) marks changes to be in the next release. Developers who have claimed items are: ------------------------------------- - * Bruce is Bruce Momjian - * Bryan is Bryan Henderson - * D'Arcy is D'Arcy J.M. Cain - * Dan is Dan McGuirk - * Daniel is Daniel Kalchev - * Darren is Darren King - * Edmund is Edmund Mergl - * Erich Stamberger - * Gerhard is Gerhard Reithofer - * Goran is Goran Thyni - * Henry is Henry B. Hotz - * Igor is Igor - * Jan is Jan Wieck - * Jun is Jun Kuwamura - * Kurt is "Kurt J. Lidl" - * Marc is Marc Fournier - * Martin is Martin S. Utesch - * Oleg is Oleg Bartunov - * Paul is Paul M. Aoki - * Patrick is Patrick van Kleef - * Peter is Peter T Mount - * Phil is Phil Thompson - * Raymond is Raymond Toy - * Soo-Ho Ok - * Stefan Simkovics - * Sven is Sven Verdoolaege - * Tatsuo is Tatsuo Ishii - * Thomas is Thomas Lockhart - * Todd is Todd Brandys is - * Vadim is "Vadim B. Mikheev" - * Vivek is Vivek Khera + * Bruce is Bruce Momjian + * Bryan is Bryan Henderson + * D'Arcy is D'Arcy J.M. Cain + * Dan is Dan McGuirk + * Daniel is Daniel Kalchev + * Darren is Darren King + * Edmund is Edmund Mergl + * Erich Stamberger + * Gerhard is Gerhard Reithofer + * Goran is Goran Thyni + * Henry is Henry B. Hotz + * Igor is Igor + * Jan is Jan Wieck + * Jun is Jun Kuwamura + * Kurt is "Kurt J. Lidl" + * Marc is Marc Fournier + * Martin is Martin S. Utesch + * Michael is Michael Meskes + * Oleg is Oleg Bartunov + * Paul is Paul M. Aoki + * Patrick is Patrick van Kleef + * Peter is Peter T Mount + * Phil is Phil Thompson + * Raymond is Raymond Toy + * Soo-Ho Ok + * Stefan Simkovics + * Sven is Sven Verdoolaege + * Tatsuo is Tatsuo Ishii + * Thomas is Thomas Lockhart + * Todd is Todd Brandys is + * Vadim is "Vadim B. Mikheev" + * Vivek is Vivek Khera -Additional; 6.3 developers include: +Additional 6.3 developers include: --------------------------------- - * Billy is Billy G. Allie - * Brook is Brook Milligan - * James is James Hughes - * Jeroen is Jeroen van Vianen - * Matt is Matt Maycock - * Ryan is Ryan Kirkpatrick - * TomH is Tom I Helbekkmo - * TomS is Tom Szybist - * Travis is Travis Melhiser + * Billy is Billy G. Allie + * Brook is Brook Milligan + * James is James Hughes + * Jeroen is Jeroen van Vianen + * Matt is Matt Maycock + * Ryan is Ryan Kirkpatrick + * TomH is Tom I Helbekkmo + * TomS is Tom Szybist + * Travis is Travis Melhiser RELIABILITY ----------- @@ -63,7 +64,8 @@ RELIABILITY * Overhaul bufmgr/lockmgr/transaction manager * -Fix CLUSTER * Remove EXTEND? -* -Aggregates on VIEW always returns zero (maybe because there is no oid for views?) +* -Aggregates on VIEW always returns zero (maybe because there is no oid for vi +ews?) * CREATE VIEW requires super-user priviledge * Can lo_export()/lo_import() read/write anywhere, causing a security problem? * Tables that start with xinv confused to be large objects @@ -79,9 +81,10 @@ RELIABILITY * UPDATE table SET table.value = 3 fails * -UPDATE key_table SET keyval=count(reftab.num) fails * -INSERT INTO ... SELECT DISTINCT ... does not accept DISTINCT -* -INSERT INTO table SELECT id, count(*) FROM table2 GROUP BY id generates error * Make pg_dump preserve inheritance column order, do non-inherits first * User who can create databases can modify pg_database table +* optimizer memory exhaustion with many OR's +* elog() does not free all its memory(Jan) ENHANCEMENTS ------------ @@ -93,31 +96,31 @@ ENHANCEMENTS * Allow transaction commits with rollback with no-fsync performance * More access control over who can create tables and access the database * Add full ANSI SQL capabilities - * -add subselects(Vadim) - * Implement HAVING clause - * -Implement EXISTS qualifier - * -report "Not implemented" if valid syntax is supplied - * add OUTER joins, left and right (Thomas) - * make VIEWs updateable where possible - * -add UNIONS(Bruce) - * add INTERSECTS, SUBTRACTS - * add temporary tables(Bruce) - * add sql3 recursive unions - * add the concept of dataspaces - * add DECIMAL, NUMERIC, DOUBLE PRECISION, BIT, BIT VARYING - * NCHAR (as distinguished from ordinary varchar), + * -add subselects(Vadim) + * Implement HAVING clause + * -Implement EXISTS qualifier + * -report "Not implemented" if valid syntax is supplied + * add OUTER joins, left and right (Thomas) + * make VIEWs updateable where possible + * -add UNIONS(Bruce) + * add INTERSECTS, SUBTRACTS + * add temporary tables(Bruce) + * add sql3 recursive unions + * add the concept of dataspaces + * add DECIMAL, NUMERIC, DOUBLE PRECISION, BIT, BIT VARYING + * NCHAR (as distinguished from ordinary varchar), * Allow compression of large fields or a compressed field type * Fix the rules system(Jan?,Soo-Ho) - * robust - * making INSTEAD rules work - * add CONSTRAINT + * robust + * making INSTEAD rules work + * add CONSTRAINT * Full set of text operations and functions - * word searches, concat,max() on text, char + * word searches, concat,max() on text, char * Large objects - * -overwriting blocks has problems(Peter) - * -there are other problems, too.(Peter) - * Fix large object mapping scheme, own reltype - * not to stuff everything as files in a single directory + * -overwriting blocks has problems(Peter) + * -there are other problems, too.(Peter) + * Fix large object mapping scheme, own reltype + * not to stuff everything as files in a single directory * Better interface for adding to pg_group * Make MONEY/DECIMAL have a defined precision * Add support for tables >2G, or test current version @@ -125,9 +128,9 @@ ENHANCEMENTS * Allow libpq to cancel query requests * Add REGEX internationalization * -Add other language types for built-in functions - * expand to allow tcl, perl, java - * generalize the function manager switch to pass - * function sources to interpreter engines. + * expand to allow tcl, perl, java + * generalize the function manager switch to pass + * function sources to interpreter engines. * -remove time-travel feature(Vadim) * -reduce system column overhead(Vadmin) * -remove pg_time table(Vadim) @@ -145,7 +148,8 @@ ENHANCEMENTS * add UNIQUE capability to non-btree indexes * make number of backends a config parameter, storage/sinvaladt.h:MaxBackendId * certain indexes will not shrink, i.e. oid indexes with many inserts -* make NULL's come out at the beginning or end depending on the ORDER BY direction +* make NULL's come out at the beginning or end depending on the ORDER BY direct +ion * change the library/backend interface to use network byte order * -allow unix domain sockets for local connections for performance and security * -Add PAGER for psql's \dt, \d, \z tablename @@ -162,13 +166,24 @@ ENHANCEMENTS * Fix compile and security of Kerberos/GSSAPI code * Allow psql to print nulls as distinct from ""(?) * Allow variable casts with BETWEEN 'today'::asbtime AND 'today'::abstime -* Allow VIEW permissions to be set separately from the underlying tables +* -Allow VIEW permissions to be set separately from the underlying tables +* Allow INSERT INTO ... SELECT ... FROM view to work * Allow text, char(), and varchar() overhead to be only 2 bytes, not 4 bytes +* Make VACUUM on database not lock pg_class +* Make VACUUM ANALYZE only use a readlock +* Allow cursors to be DECLAREd/OPENed/CLOSEed outside transactions +* Allow installation data block size and max tuple size configuration(Darren) +* Allow views on a UNION +* Allow views of aggregate columns +* Allow variable block sizes(Darren) +* System tables are now more update-able from SQL(Jan) +* New pg_shadow file, pg_user is now a view of pg_shadow(Jan) PERFORMANCE ----------- -* Use indexes in ORDER BY, min(), max() -* -Allow LIKE/wildcard matches to use indexes if the wildcard character is not first +* Use indexes in ORDER BY, min(), max()(Costin Oproiu) +* -Allow LIKE/wildcard matches to use indexes if the wildcard character is not +first * Optimizing disjunctive queries * Fix bushy-plans (Martin) * Other optimizer bugs @@ -181,6 +196,8 @@ PERFORMANCE * update pg_statistic table to remove operator column * make index creation use psort code, because it is now faster(Vadim) * remove fork()/exec() of backend and make it just fork() +* Improve vacuum locking issues +* Add base table name to \d index DOCUMENTATION ------------- @@ -195,33 +212,6 @@ DOCUMENTATION CHANGES IN THE 6.3 RELEASE -------------------------- -Developers who have claimed items are: -------------------------------------- - * Billy is Billy G. Allie - * Brook is Brook Milligan - * Bruce is Bruce Momjian - * D'Arcy is D'Arcy J.M. Cain - * Dan is Dan McGuirk - * Darren is Darren King - * Goran is Goran Thyni - * Henry is Henry B. Hotz - * James is James Hughes - * Jan is Jan Wieck - * Jeroen is Jeroen van Vianen - * Marc is Marc Fournier - * Martin is Martin S. Utesch - * Matt is Matt Maycock - * Peter is Peter T Mount - * Phil is Phil Thompson - * Ryan is Ryan Kirkpatrick - * Tatsuo is Tatsuo Ishii - * Thomas is Thomas Lockhart - * TomH is Tom I Helbekkmo - * TomS is Tom Szybist - * Todd is Todd Brandys is - * Travis is Travis Melhiser - * Vadim is "Vadim B. Mikheev" - Bug Fixes --------- Fix binary cursors broken by MOVE implementation(Vadim) @@ -241,44 +231,47 @@ Fix for count(*), aggs with views and multiple tables and sum(3)(Bruce) Fix cluster(Bruce) Fix for PQtrace start/stop several times(Bruce) Fix a variety of locking problems like newer lock waiters getting - lock before older waiters, and having readlock people not share - locks if a writer is waiting for a lock, and waiting writers not - getting priority over waiting readers(Bruce) + lock before older waiters, and having readlock people not share + locks if a writer is waiting for a lock, and waiting writers not + getting priority over waiting readers(Bruce) Fix crashes in psql when executing queries from external files(James) Fix problem with multiple order by columns, with the first one having - NULL values(Jeroen) + NULL values(Jeroen) Use correct hash table support functions for float8 and int4(Thomas) Re-enable JOIN= option in CREATE OPERATOR statement (Thomas) Change precedence for boolean operators to match expected behavior(Thomas) Generate elog(ERROR) on over-large integer(Bruce) Allow multiple-argument functions in constraint clauses(Thomas) Check boolean input literals for 'true','false','yes','no','1','0' - and throw elog(ERROR) if unrecognized(Thomas) - + and throw elog(ERROR) if unrecognized(Thomas) +Major large objects fix Enhancements ------------ -Real deadlock detection, no more timeouts(Bruce) - Subselects with EXISTS, IN, ALL, ANY keywords (Vadim, Bruce, Thomas) -Add SQL92 "constants" CURRENT_DATE, CURRENT_TIME, CURRENT_TIMESTAMP, - CURRENT_USER(Thomas) +Subselects with EXISTS, IN, ALL, ANY keywords (Vadim, Bruce, Thomas) +New User Manual(Thomas, others) Speedup by inlining some frequently-called functions +Real deadlock detection, no more timeouts(Bruce) +Add SQL92 "constants" CURRENT_DATE, CURRENT_TIME, CURRENT_TIMESTAMP, + CURRENT_USER(Thomas) Modify constraint syntax to be SQL92-compliant(Thomas) Implement SQL92 PRIMARY KEY and UNIQUE clauses using indices(Thomas) Recognize SQL92 syntax for FOREIGN KEY. Throw elog notice(Thomas) -Allow NOT NULL UNIQUE constraint clause (each allowed separately before)(Thomas) +Allow NOT NULL UNIQUE constraint clause (each allowed separately before)(Thomas +) Allow Postgres-style casting ("::") of non-constants(Thomas) Add support for SQL3 TRUE and FALSE boolean constants(Thomas) Support SQL92 syntax for IS TRUE/IS FALSE/IS NOT TRUE/IS NOT FALSE(Thomas) Allow shorter strings for boolean literals (e.g. "t", "tr", "tru")(Thomas) Allow SQL92 delimited identifiers(Thomas) -Implement SQL92 binary and hexadecimal string decoding (b'10' and x'1F')(Thomas) +Implement SQL92 binary and hexadecimal string decoding (b'10' and x'1F')(Thomas +) Support SQL92 syntax for type coercion of literal strings - (e.g. "DATETIME 'now'")(Thomas) + (e.g. "DATETIME 'now'")(Thomas) Add conversions for int2, int4, and OID types to and from text(Thomas) Use shared lock when building indices(Vadim) Free memory allocated for an user query inside transaction block after - this query is done, was turned off in <= 6.2.1(Vadim) + this query is done, was turned off in <= 6.2.1(Vadim) New SQL statement CREATE PROCEDURAL LANGUAGE(Jan) New PostgreSQL Procedural Language (PL) backend interface(Jan) Rename pg_dump -H option to -h(Bruce) @@ -294,12 +287,13 @@ Augment support for SQL92 SET TIME ZONE...(Thomas) SET/SHOW/RESET TIME ZONE uses TZ backend environment variable(Thomas) Implement SET keyword = DEFAULT and SET TIME ZONE DEFAULT(Thomas) Enable SET TIME ZONE using TZ environment variable(Thomas) -Add PGDATESTYLE environment variable to frontend and backend initialization(Thomas) +Add PGDATESTYLE environment variable to frontend and backend initialization(Tho +mas) Add PGTZ, PGCOSTHEAP, PGCOSTINDEX, PGRPLANS, PGGEQO - frontend library initialization environment variables(Thomas) + frontend library initialization environment variables(Thomas) Regression tests time zone automatically set with "setenv PGTZ PST8PDT"(Thomas) Add pg_description table for info on tables, columns, operators, types, and - aggregates(Bruce) + aggregates(Bruce) Increase 16 char limit on system table/index names to 32 characters(Bruce) Rename system indices(Bruce) Add 'GERMAN' option to SET DATESTYLE(Thomas) @@ -310,7 +304,7 @@ Implement day of year as possible input to date_part()(Thomas) Define timespan_finite() and text_timespan() functions(Thomas) Remove archive stuff(Bruce) Allow for a pg_password authentication database that is separate from - the system password file(Todd) + the system password file(Todd) Dump ACLs, GRANT, REVOKE permissions(Matt) Define text, varchar, and bpchar string length functions(Thomas) Fix Query handling for inheritance, and cost computations(Bruce) @@ -321,7 +315,6 @@ Add UNION, GROUP, DISTINCT to INSERT(Bruce) varchar() stores only necessary bytes on disk(Bruce) Fix for BLOBs(Peter) Mega-Patch for JDBC...see README_6.3 for list of changes(Peter) -Allow installation data block size and max tuple size configuration(Darren) Remove unused "option" from PQconnectdb() New LOCK command and lock manual page describing deadlocks(Bruce) Add new psql \da, \dd, \df, \do, \dS, and \dT commands(Bruce) @@ -336,8 +329,17 @@ Add Unix socket support to DBD::Pg(Goran) New python interface (PyGreSQL 2.0)(D'Arcy) New frontend/backend protocol has a version number, network byte order(Phil) Security features in pg_hba.conf enhanced and documented, many cleanups(Phil) -New HTML and Postscript documentation(Thomas) - +CHAR() now faster access than VARCHAR() or TEXT +ecpg embedded SQL preprocessor +Add GROUP BY to INSERT INTO table SELECT * FROM table2 +Reduce system column overhead(Vadmin) +Remove pg_time table(Vadim) +Add pg_type attribute to identify types that need length (bpchar, varchar) +Add report of offending line when COPY command fails +Allow VIEW permissions to be set separately from the underlying tables. + For security, use GRANT/REVOKE on views as appropriate(Jan) +Tables now have no default GRANT SELECT TO PUBLIC. You must + explicitly grant such permissions. Source Tree Changes ------------------- @@ -349,7 +351,7 @@ Make configure more automated(Brook) Add script to check regression test results Break parser functions into smaller files, group together(Bruce) Rename heap_create to heap_create_and_catalog, rename heap_creatr - to heap_create()(Bruce) + to heap_create()(Bruce) Sparc/Linux patch for locking(TomS) Remove PORTNAME and reorganize port-specific stuff(Marc) Add optimizer README file(Bruce) @@ -358,7 +360,7 @@ Fix for NetBSD locking(Henry) Fix for libptcl make(Tatsuo) AIX patch(Darren) Change IS TRUE, IS FALSE, ... to expressions using "=" rather than - function calls to istrue() or isfalse() to allow optimization(Thomas) + function calls to istrue() or isfalse() to allow optimization(Thomas) Various fixes NetBSD/Sparc related(TomH) Alpha linux locking(Travis,Ryan) Change elog(WARN) to elog(ERROR)(Bruce) @@ -374,3 +376,5 @@ Start an AUX port Start a Cygnus port Add string functions to regression suite(Thomas) Expand a few function names formerly truncated to 16 characters(Thomas) +Remove un-needed malloc() calls and replace with palloc()(Bruce) + diff --git a/migration/6.2.1_to_6.3 b/migration/6.2.1_to_6.3 index 65c433334d..12921aab7a 100644 --- a/migration/6.2.1_to_6.3 +++ b/migration/6.2.1_to_6.3 @@ -1,15 +1,60 @@ This migration requires a complete dump of the 6.2 or 6.2.1 database and a restore of the database in 6.3. -In addition, 6.3 has separate permissions for views, rather than relying -on the permissions set on the underlying tables. For this reason, you will -have to set permissions on your views if you want anything but the default -permissions. +There are some general 6.3 issues that I want to mention. These are +only the big items that can not be described in one sentence. A review +of the HISTORY files is still needed. -6.3 has had its default permissions on a table set such that unless you -are the owner, when a table is created, other users of the system won't -have access to them. You *must* do a 'GRANT' for each table you wish open -to other ppl. +First, we now have subselects. Now that we have them, I would like to +mention that without subselects, SQL is a very limited language. +Subselects are a major feature, and you should review your code for +places where subselects provide a better solution for your queries. I +think you will find that there are more uses for subselects than you may +think. Vadim has put us on the big SQL map with subselects, and fully +functional ones too. The only thing you can't do with subselects is to +use them in the target list. -Those migrating from earlier 1.* releases should first upgrade to 1.09 -because the COPY output format was improved from the 1.02 release. +Second, 6.3 uses unix domain sockets rather than TCP/IP by default. To +enable connections from other machines, you have to use the new +postmaster -i option, and of course edit pg_hba.conf. Also, for this +reason, the format of pg_hba.conf has changed. + +Third, char() fields will now allow faster access than varchar() or +text. Specifically, the text and varchar() have a penalty for access to +any columns after the first column of this type. char() used to also +have this access penalty, but it no longer does. This may suggest that +you redesign some of your tables, especially if you have short character +columns that you have defined as varchar() or text. This and other +changes make 6.3 even faster than earlier releases. + +We now have passwords definable independent of any Unix file. There are +new SQL USER commands. See the pg_hba.conf manual page for more +information. There is a new table, pg_shadow, which is used to store +user information and user passwords, and it by default only SELECT-able +by the postgres super-user. pg_user is now a view of pg_shadow, and is +SELECT-able by PUBLIC. You should keep using pg_user in your +application without changes. + +User-created tables now no longer have SELECT permission to PUBLIC by +default. This was done because the ANSI standard requires it. You can +of course GRANT any permissions you want after the table is created. +System tables continue to be SELECT-able by PUBLIC. + +We also have real deadlock detection code. No more sixty-second +timeouts. And the new locking code implements a FIFO better, so there +should be less resource starvation during heavy use. For performance +reasons, time travel is gone, but can be implemented using triggers (see +pgsql/contrib/spi/README). Please check out the new \d command for +types, operators, etc. Also, views have their own permissions now, not +based on the underlying tables, so permissions on them have to be set +separately. Check /pgsql/interfaces for some new ways to talk to +PostgreSQL. + +This is the first release that really required an explaination for +existing users. In many ways, this was necessary because the new +release removes many limitations, and the work-arounds people were using +are no longer needed. + +Long live PostgreSQL. + +-- Bruce Momjian diff --git a/register.txt b/register.txt index b6e0bb1729..9e976333e3 100644 --- a/register.txt +++ b/register.txt @@ -1,6 +1,6 @@ -(1998-02-01) +(1998-03-01) PostgreSQL has a Web site at http://www.postgresql.org/ which carries details on the latest release, upcoming features, and other information to make your work or play with PostgreSQL more productive.