7.3 JDBC Configuration

This section describes additional configuration which must be done to allow TOPCAT to access SQL-compatible relational databases for reading (see Section 3.1.5) or writing (see Section 3.2.6) tables. If you don't need to talk to SQL-type databases, you can ignore the rest of this section. The steps described here are the standard ones for configuring JDBC (which sort-of stands for Java Database Connectivity), described in more detail on Sun's JDBC web page.

To use TOPCAT with SQL-compatible databases you must:

• Have access to an SQL-compatible database locally or over the network
• Have a JDBC driver appropriate for that database
• Install this driver for use with TOPCAT
• Know the format the driver uses for URLs to access database tables
• Have appropriate privileges on the database to perform the desired operations

1. Set the jdbc.drivers system property to the name of the driver class as described in Section 7.2.1
2. Ensure that the classpath you are using includes this driver class as described in Section 7.2.3

These steps are all standard for use of the JDBC system.

To the author's knowledge, TOPCAT has so far successfully been used with the following RDBMSs and corresponding JDBC drivers:

MySQL

MySQL 3.23.55 on Linux has been tested with the Connector/J driver version 3.0.8 and seems to work, though tables with very many (hundreds of) columns cannot be written owing to SQL statement length restrictions. Note there is known to be a column metadata bug in version 3.0.6 of the driver which can cause a ClassCastException error when tables are written.

PostgreSQL

PostgreSQL 7.4.1 apparently works with its own driver.