External tables are database tables in an external source, such as tables in a PostgreSQL database. Before you can add an external table as a source, you first need to create an external connection with the database. See the topic StreamLab External Connections Overview for more details.
On the Sources page, drag an External Table source from the left column into the center area.
Click the new External Table source.
The Edit External Table Source page opens.
By default, StreamLab uses the project schema for the new source. You can also select a schema from the pulldown menu on the left.
Select a stream from the pulldown menu on the right. This is the stream into which lines from the external table source will be read.
Select an External Connection, such as a PostgreSQL_DB.
Enter the database schema for the external table. (That is, the PostgreSQL schema.)
Enter the name of the external table (That is, the PostgreSQL table name.)
Next, enter columns for the table. Column names need to match those in the external database. You can also click the Discover Columns button to add columns automatically. Note that you can also use the Paste option for column Lists.
Test the source by clicking the1. Sample 5 Rows from Source button.
Click the Go Up arrow to exit the Edit Source page.