7.16. Oracle Connector

The Oracle connector allows querying and creating tables in an external Oracle database. This can be used to join data between different systems like Oracle and Hive, or between two different Oracle instances.

Configuration

To configure the Oracle connector, create a catalog properties file in etc/catalog named, for example, oracle.properties, to mount the Oracle connector as the oracle catalog. Create the file with the following contents, replacing the connection properties as appropriate for your setup:

  1. connector.name=oracle
  2. connection-url=jdbc:oracle:thin:@example.net:1521/ORCLCDB
  3. connection-user=root
  4. connection-password=secret

Multiple Oracle Servers

You can have as many catalogs as you need, so if you have additional Oracle servers, simply add another properties file to etc/catalog with a different name (making sure it ends in .properties). For example, if you name the property file sales.properties, Presto will create a catalog named sales using the configured connector.

Querying Oracle

The Oracle connector provides a schema for every Oracle database. You can see the available Oracle databases by running SHOW SCHEMAS:

  1. SHOW SCHEMAS FROM oracle;

If you have a Oracle database named web, you can view the tables in this database by running SHOW TABLES:

  1. SHOW TABLES FROM oracle.web;

You can see a list of the columns in the clicks table in the web database using either of the following:

  1. DESCRIBE oracle.web.clicks;
  2. SHOW COLUMNS FROM oracle.web.clicks;

Finally, you can access the clicks table in the web database:

  1. SELECT * FROM oracle.web.clicks;

If you used a different name for your catalog properties file, use that catalog name instead of oracle in the above examples.

Oracle Connector Limitations

The following SQL statements are not yet supported: