Configuring Retention Time for Materialized Views
When creating Materialized Views, you can configure how the system should retain the data rows in the Materialized Views. You can either choose between retaining the data by time or the row count.
- Retention Time
- Min Row Retention Count
You can specify the Retention Time and Min Row Retention Count when creating a Materialized View for a SQL job on the Compose page of the Streaming SQL Console.
Retention Time is specified in seconds, and it tells the system to retain data rows as old as the specified retention time. The rows that are outside of the retention time are removed from the Materialized View.
Minimum Row Retention Count
The Min Row Retention Count parameter indicated to the system to maintain a specific number of data rows in the Materialized View.
The following example shows how to configure the system to retain the last 5000 data rows. This means that only the first 5000 data rows are included in the Materialized View, and the data rows from 5001 are removed from the Materialized View.
Retaining all data without limit
In order to retain all data rows, regardless of time, or number of rows in the Materialized View, both settings can be reset to zero (0). This indicates to the system that all data must be preserved without a time limit.
The following example shows how to configure the Retention parameters to keep all of the data regardless of time: