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:

connector.name=oracle
# The correct syntax of the connection-url varies by Oracle version and
# configuration. The following example URL connects to an Oracle SID named
# "orcl".
# In some situations, the connection-url has to include the user and password.
# example: connection-url=jdbc:oracle:thin:user/password@example.net:1521:orcl
#
connection-url=jdbc:oracle:thin:@example.net:1521:orcl
connection-user=root
connection-password=secret

The connection-url defines the connection information and parameters to pass to the JDBC driver. The Oracle connector uses the Oracle JDBC Thin driver, and the syntax of the URL may be different depending on your Oracle configuration. For example, the connection URL is different if you are connecting to an Oracle SID or an Oracle service name. See the Oracle Database JDBC driver documentation for more information.

The connection-user and connection-password are typically required and determine the user credentials for the connection, often a service user.

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.

General Configuration Properties#

Property Name

Description

Default

user-credential-name

Name of the extraCredentials property whose value is the JDBC driver’s user name. See extraCredentials in Parameter Reference.

password-credential-name

Name of the extraCredentials property whose value is the JDBC driver’s user password. See extraCredentials in Parameter Reference.

case-insensitive-name-matching

Match dataset and table names case-insensitively.

false

case-insensitive-name-matching.cache-ttl

Duration for which remote dataset and table names will be cached. Set to 0ms to disable the cache.

1m

Querying Oracle#

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

SHOW SCHEMAS FROM oracle;

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

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:

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

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

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: