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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 Oct 9 23:14:53 EDT 2002 |
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Last updated: Fri Oct 11 00:59:31 EDT 2002 |
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Current maintainer: Bruce Momjian (pgman@candle.pha.pa.us) |
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@ -96,6 +96,8 @@ |
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4.25) How do I return multiple rows or columns from a function? |
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4.26) Why can't I reliably create/drop temporary tables in PL/PgSQL |
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functions? |
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4.27) What replication options are available? |
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4.28) What encryption options are available? |
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Extending PostgreSQL |
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@ -1046,12 +1048,13 @@ SELECT * |
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4.24) How do I perform queries using multiple databases? |
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There is no way to query any database except the current one. Because |
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PostgreSQL loads database-specific system catalogs, it is uncertain |
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how a cross-database query should even behave. |
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There is no way to query a database other than the current one. |
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Because PostgreSQL loads database-specific system catalogs, it is |
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uncertain how a cross-database query should even behave. |
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Of course, a client can make simultaneous connections to different |
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databases and merge the information that way. |
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/contrib/dblink allows cross-database queries using function calls. Of |
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course, a client can make simultaneous connections to different |
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databases and merge the results on the client side. |
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4.25) How do I return multiple rows or columns from a function? |
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@ -1070,6 +1073,25 @@ SELECT * |
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the old temporary table. The solution is to use EXECUTE for temporary |
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table access in PL/PgSQL. This will cause the query to be reparsed |
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every time. |
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4.27) What replication options are available? |
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There are several master/slave replication solutions available. These |
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allow only the master to make database changes and the slave can only |
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do database reads. The bottom of |
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http://gborg.postgresql.org/genpage?replication_research lists them. A |
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multi-master replication solution is being worked on at |
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http://gborg.postgresql.org/project/pgreplication/projdisplay.php. |
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4.27) What encryption options are available? |
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* /contrib/pgcrypto contains many encryption functions for use in |
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SQL queries. |
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* The only way to encrypt transmission from the client to the server |
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is by using hostssl in pg_hba.conf. |
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* Database user passwords are automatically encrypted when stored in |
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version 7.3. In previous versions, you must enable |
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password_encryption in postgresql.conf. |
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_________________________________________________________________ |
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Extending PostgreSQL |
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