Delete a table Administrators can delete custom tables that are no longer needed. For example, delete a table from an application that is under development because the business requirements change. A table is custom if an administrator created it and it is not part of a system upgrade or plugin activation. Custom table names always begins with u_. Base system tables cannot be deleted. Also, any missing base system tables are recreated when the instance is upgraded. If another table extends to it, you cannot delete a table. Warning: You must delete the records in the table before you delete the table. If you do not delete the records first, errors can result on the parent table if it references the records. Deleting the records removes any references from the parent table. Delete a custom tableIf you no longer need a custom table, you can delete it after you delete all the records in the table.