Data Quality is calculated and aggregated every one hour, including all events that arrive in the database within the same hour. For example, the aggregated information at 10:00 AM includes all data from 10:00:00.000 to 10:59:59.999, inclusively. The time of the aggregation process depends on when the product was installed or upgraded:
During a fresh installation, the process creates a new table to store Data Quality overtime with data sources information. The feature schedules the aggregation process at the tenth minute of every hour. For example, if a fresh install was performed at 9:15:00 AM, the aggregation would be scheduled to execute at 10:10:00 AM and every one hour after that.
After an upgrade, previous data will be dropped because they are no longer relevant to new categories. For example, if an upgrade was performed at 9:15:00 AM, the aggregation would be scheduled to execute at 10:10:00 AM to aggregate all events from 9:00:00.000 to 9:59:59.999 AM, inclusive. Then it will run every one hour after that.
If you switch to a different database, you would need to wait for a few minutes before accessing the Data Quality page again.