SQL Query Dialogue
If you want to read a table from an SQL database, you can use a specialised dialogue to specify the SQL query by selecting SQL Query button from the Load Window's toolbar () or DataSources menu.
This provides you with a list of fields to fill in which make up the query, as follows:
mysql" for MySQL's Connector/J driver or "
postgresql" for PostgreSQL's JDBC driver.
localhost" if the database is local).
SELECT * from XXX". In principle any SQL query on the database can be used here, but the details of what SQL syntax is permitted may be restricted by the JDBC driver you are using.
There are a number of criteria which must be satisfied for SQL access to work within TOPCAT (installation of appropriate drivers and so on) - see Section 10.3. If you don't take these steps, this dialogue may be inaccessible.
The way that this dialogue contacts the database makes some assumptions about how the JDBC driver works which are not always true, so for some databases and drivers it may not be possible to get it to work. It may be improved in the future; if you have particular problems, please contact the author or the mailing list.