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@ -1,7 +1,7 @@ |
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Frequently Asked Questions (FAQ) for PostgreSQL |
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Last updated: Wed Dec 15 20:06:34 EST 2004 |
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Last updated: Fri Dec 17 23:12:56 EST 2004 |
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Current maintainer: Bruce Momjian (pgman@candle.pha.pa.us) |
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@ -262,8 +262,9 @@ |
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a collection of PostgreSQL technical articles at |
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http://techdocs.PostgreSQL.org/. |
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psql has some nice \d commands to show information about types, |
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operators, functions, aggregates, etc. |
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The command line client program psql has some \d commands to show |
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information about types, operators, functions, aggregates, etc. - use |
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\? to display the available commands. |
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Our web site contains even more documentation. |
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@ -327,20 +328,15 @@ |
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reduce lock contention. |
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Performance |
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PostgreSQL has performance similar to other commercial and open |
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source databases. it is faster for some things, slower for |
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PostgreSQL's performance is comparable to other commercial and |
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open source databases. It is faster for some things, slower for |
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others. In comparison to MySQL or leaner database systems, we |
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are faster for multiple users, complex queries, and a |
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read/write query load. MySQL is faster for simple SELECT |
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queries done by a few users. Of course, MySQL does not have |
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most of the features mentioned in the Features section above. |
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We are built for reliability and features, and we continue to |
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improve performance in every release. There is an interesting |
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Web page comparing PostgreSQL to MySQL at |
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http://openacs.org/philosophy/why-not-mysql.html Also, MySQL is |
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is a company that distributes its products via open source, and |
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requires a commercial license for close-source software, not an |
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open source development community like PostgreSQL. |
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improve performance in every release. |
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Reliability |
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We realize that a DBMS must be reliable, or it is worthless. We |
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@ -384,10 +380,10 @@ |
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item is solely to support the PostgreSQL project and does not fund any |
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specific company. If you prefer, you can also send a check to the |
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contact address. |
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_________________________________________________________________ |
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Also, if you have a success story about PostgreSQL, please submit it |
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to our advocacy site at http://advocacy.postgresql.org. |
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_________________________________________________________________ |
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User Client Questions |
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@ -420,7 +416,7 @@ |
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2.3) Does PostgreSQL have a graphical user interface? |
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Yes, there are several graphical interfaces to PostgreSQL available. |
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These include PgAccess http://www.pgaccess.org), PgAdmin III |
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These include PgAccess http://www.pgaccess.org), pgAdmin III |
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(http://www.pgadmin.org, RHDB Admin (http://sources.redhat.com/rhdb/ |
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), TORA (http://www.globecom.net/tora/ (partly commercial), and Rekall |
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( http://www.thekompany.com/products/rekall/, proprietary). There is |
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@ -521,9 +517,9 @@ |
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exceeded your kernel's limit on shared memory space. Each buffer is 8K |
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and the default is 1000 buffers. |
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You can also use the sort_mem and work_mem options to increase the |
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maximum amount of memory used by the backend processes for each |
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temporary sort. The default is 1024 (i.e. 1MB). |
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You can also use the sort_mem (from PostgreSQL 8.0: work_mem) options |
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to increase the maximum amount of memory used by the backend processes |
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for each temporary sort. The default is 1024 (i.e. 1MB). |
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You can also use the CLUSTER command to group data in tables to match |
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an index. See the CLUSTER manual page for more details. |
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@ -944,9 +940,8 @@ BYTEA bytea variable-length byte array (null-byte safe) |
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Finally, you could use the OID returned from the INSERT statement to |
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look up the default value, though this is probably the least portable |
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approach, and the oid value will wrap around when it reaches 4 |
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billion. In Perl, using DBI with Edmund Mergl's DBD::Pg module, the |
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oid value is made available via $sth->{pg_oid_status} after |
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$sth->execute(). |
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billion. In Perl, using DBI with the DBD::Pg module, the oid value is |
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made available via $sth->{pg_oid_status} after $sth->execute(). |
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4.15.3) Doesn't currval() lead to a race condition with other users? |
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