As of DB2 10 NFM, the Real-Time Statistics logic has been extended to cope with mass delete operations more accurate. Before DB2 10 NFM, the MASSDELETE counters have been incremented after a mass delete operation.
SYSIBM.SYSTABLESPACESTATS.TOTALROWS counter will now be reset to 0 in case of a mass delete for a single table table space scenario. The same applies for SYSIBM.SYSINDEXSPACESTATS.TOTALENTRIES counter.
A multi table table-space scenario is an exception. As the Real-Time Statistics information is based on page set level, DB2 does not know how many rows are associated to the table the mass delete was operated on. In this case, the SYSIBM.SYSTABLESPACESTATS.MASSDELETE counter will be still incremented in past DB2 10 NFM and SYSIBM.SYSTABLESPACESTATS.TOTALROWS will be invalidated (set to NULL).
SYSIBM:SYSINDEXSPACESTATS is not affected by multi table table spaces, as an index is always only associated to a single table.
However, an APAR will be opened to be consistent with SYSIBM.SYSTABLESPACESTATS, that will change logic to increment the SYSIBM.SYSINDEXSPACESTATS.MASSDELETE counters also.