Deletes rows in a data extension with column values specified in name value pairs. Returns the number of rows affected. You can also use this function with SMS data.

DeleteData(1, 2, 3)

1stringRequiredName of data extension from which to delete specified row
2stringRequiredName of column used to identify rows to delete.
3stringRequiredValue used to identify rows to delete.

The system deletes rows in the SendDE data extension whose _SubscriberKey column contains the value 12345 and returns the number of rows that were deleted.