External catalog

This feature is not available in the local mode

External catalog enables users to connect their catalog databases to Akridata Data Explorer and create virtual tables (views) by joining internal catalog information with the catalog information present in the external catalog. This enables a unified view of the catalog information for rich querying and visualization capabilities.

The External catalog page is available at 'Data -> Repo' on the left navigation panel, as shown below.

The page shows a listing of all registered external catalogs as shown below:

Add External Catalog

The following types of External catalogs can be added (registered) to Data Explorer.

1. MySQL
2. SQL Server
3. PostgreSQL
4. AWS Athena - This requires an Athena workgroup with an S3 bucket to store query results to be set up as a pre-requisite. Please refer to AWS documentation here.

To add an external catalog:

1. Click on the 'Add External Catalog' button.
2. Fill Name and Description in the form provided.
3. Select the type of external catalog from the drop-down.
4. The form fields will be updated based on the type selected to capture type-specific information. The type-specific form fields are described below. 
   1. MYSQL - Hostname and Port. All DB schemas within this database endpoint become accessible.
   2. PostgreSQL - Hostname, Port, and DB name of the database schema to connect.
   3. SQLServer -  Hostname, Port, and DB name of the database schema to connect.
   4. Athena
      1. Region - The AWS region(e.g., us-east-1) where the AWS Athena instance is hosted.
      2. Data Source - Name of AWS Athena DataSource available on the AWS console.
      3. Workgroup - Name of AWS Athena workgroup that is configured as a pre-requisite.
5. Leave the 'SMS Namespace' field as default.
6. In the SMS Key field, select a secret that holds the credentials. The secret must have been registered on the Secrets page.
   1. MYSQL, PostgreSQL, and SQLServer support a 'Basic Auth' type of secret.
   2. AWS Athena supports 'Basic Auth' and 'AWS' types of secret. The 'AWS' type of secret is recommended.
7. Click on 'Save' to register the external catalog.

Edit External Catalog

On the card corresponding to the external catalog to be edited, click on the 'Edit' button. The form shows fields similar to 'Add Catalog' with only a few fields allowed for editing. Once edited, click on the 'Save' button.

View External catalog

The 'View' operation is used to browse the schema of a registered external catalog. On the card corresponding to the external catalog to be viewed, click the 'View' button. The following page is presented with a listing of all the databases schemas that are accessible. Clicking on the 'down' arrows expands the next level of tables and columns, as shown below for the 'voc2012' database schema.

Delete External catalog

A registered external catalog can be deleted(unregistered) by clicking on the 'Delete' button available on the external catalog card. This action will result in all views defined using this external catalog table becoming unusable.