Looker

Prerequisites

• Your Exasol database must be running and reachable from the environment where Looker is used.

• The Exasol JDBC driver must be installed. To learn more, see JDBC Driver.

Create a database user

1. In the Exasol database, create a designated user for Looker and grant the user the permission to create sessions, and the appropriate permissions on the tables or schema that Looker will use.

   Example:

   Copy

   CREATE USER LOOKER IDENTIFIED BY "<password>";
   GRANT CREATE SESSION TO LOOKER;
   GRANT SELECT ON <tables> TO LOOKER;
   // or
   GRANT ALL PRIVILEGES ON SCHEMA <MY_SCHEMA> TO LOOKER;

2. A persistent derived table (PDT) is a derived table that is written to a scratch schema on your database and regenerated by a scheduled cron job. If you are planning to use PDTs in the Looker connection, create a designated schema for this purpose and grant all privileges on this schema to the Looker user.

   Example:

   Copy

   CREATE SCHEMA LOOKER_SCRATCH;
   ALTER SCHEMA LOOKER_SCRATCH CHANGE OWNER LOOKER;

   To learn more about persistent derived tables (PDTs), refer to the Looker documentation.

Connect Looker to Exasol

In Looker, create a new database connection with the following properties:

• Dialect: Exasol

• Host:Port: The hostname or IP address to the database, and the Exasol database port (default: 8563).

• Database: The name of the Exasol database.

• Username: The username for the Looker user in the Exasol database.

• Password: The password for the user.

• Schema: The schema that Looker will use in your database.

• Persistent Derived Tables: Enables persistent derived tables (PDTs).

• Temp Database: The schema that Looker will use for persistent derived tables (PDTs). This parameter is required if the PDT option is enabled.

• Additional Params: You can include additional JDBC parameters for your queries here if needed.

• PDT and Datagroup Maintenance Schedule: You can provide a cron expression that tells Looker how often it should check for datagroups and persistent derived tables (PDTs) to be regenerated or dropped. The default value is */5**** (check every 5 minutes).

• SSL: Choose whether or not you want to use SSL encryption to protect data.

• Max Connections: The maximum number of connections that Looker can establish with your database.

• Connection Pool Timeout: The time in seconds that a request will wait before the connection times out.

• SQL Runner Precache: If enabled, all table information is pre-loaded when you select a connection and schema. This allows table columns to be displayed faster when you click on a table name.