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For more information about this problem, see the MySQL reference manual.
"Cannot delete or update a parent row" error
Removing large amounts of old data may be time-consuming if during the removal License Statistics queries a license server and, as a result, updates table data. In such situations, you may see a MySQL error similar to the following:
Cannot delete or update a parent row: a foreign key constraint fails (on AggregatedUserUsage table).
To resolve this issue, you can temporarily disable the license server using the Realtime License Servers tab in the Administration page and start deleting data. If you have many license servers for which you want to delete data, contact X-Formation Support for assistance.