| <?xml version="1.0"?> |
| |
| <document> |
| <properties> |
| <title>PostgreSQL Howto</title> |
| <author email="nissim@nksystems.com">Nissim Karpenstein</author> |
| </properties> |
| |
| <body> |
| |
| <section name="PostgreSQL Howto"> |
| |
| <p> |
| Turbine comes with a default User implementation which utilizes some libraries, |
| and code that are not 100% compatible with <a href="http://www.postgresql.org"> |
| PostgreSQL</a>. This document will explain what you need to get the defaut |
| Turbine User Implementation running with PostgreSQL. The user management code is |
| only a small part of Turbine, and the default implementation is easily |
| replacable. Rather than following the steps in this document, you can always |
| create your own User implementation which does not require large object support. |
| </p> |
| |
| </section> |
| |
| <section name="JDBC Driver"> |
| |
| <p> |
| First of all, the TurbineUser class which comes with Turbine uses a hashtable |
| to store data relevant to the user. Any data in this hashtable which does |
| not map to one of the columns in the visitor table is written to a large |
| object field in the database. Database actions in the TurbineUserPeer and |
| BasePeer classes are done through the |
| <a href="http://www.working-dogs.com/village/">Village API</a>. |
| The village API uses the ResultSetMetaData returned by your JDBC driver to |
| determine the types of the columns in a SQL result set. Unfortunately, |
| in PostgreSQL large objects are referenced using an OID column (which is a |
| pointer to the data), and the metadata in the JDBC driver says that columns |
| of type OID are java.sql.Types.INTEGER. |
| </p> |
| |
| <p> |
| There is also a bug in the released versions of the PostgreSQL which causes |
| problems when reading and writing Timestamps. This is fixed in CVS. So to |
| run Turbine with PostgreSQL you need to get the latest JDBC driver code from |
| the PostgreSQL CVS server: :pserver:anoncvs@postgresql.org:/home/projects/pgsql/cvsroot |
| the password is postgresql. Before compiling the driver though, you must apply |
| a patch so the metadata says that OID columns are java.sql.Types.VARBINARY, not |
| java.sql.Types.INTEGER. <strong>Important: If you need the metadata to report |
| that OID columns are integers for another application, this patch will break |
| that app.</strong> If you've never heard of an OID before, or you only use OID's |
| to reference large objects, you don't need to worry about it. |
| </p> |
| |
| </section> |
| |
| <section name="Patch"> |
| <p> |
| This patch may or may not be necessary. If you are having problems with |
| the driver, please try it out. You may also wish to try upgrading to a |
| more recent version of the Postgrest driver and also make sure that you |
| are using the latest released version of Village. |
| </p> |
| |
| <source><![CDATA[ |
| /home/projects/pgsql/cvsroot/pgsql/src/interfaces/jdbc/org/postgresql/Field.java,v |
| retrieving revision 1.1 |
| diff -r1.1 Field.java |
| 118c118 |
| < "int4","oid", |
| --- |
| > "int4", |
| 129c129,130 |
| < "abstime","timestamp" |
| --- |
| > "abstime","timestamp", |
| > "oid" |
| 141c142 |
| < Types.INTEGER,Types.INTEGER, |
| --- |
| > Types.INTEGER, |
| 152c153,154 |
| < Types.TIMESTAMP,Types.TIMESTAMP |
| --- |
| > Types.TIMESTAMP,Types.TIMESTAMP, |
| > Types.VARBINARY |
| ]]></source> |
| |
| <p> |
| After applying that patch, compile the driver, and you should be ready to go. |
| One more problem though is that all actions involving large objects in |
| PostgreSQL require transactions. There is code in CVS now which automatically |
| sets up the transaction if necessary, so make sure you're running the recent |
| snapshots. |
| </p> |
| |
| </section> |
| |
| </body> |
| </document> |
