I discussed hashing in my earlier post. The hash organization requires additional storage. When the real-time statistics REORGHASHACCES is very low, then you need to remove the Hash organization from the table.
ALTER TABLE can be used to change the space for Hash.
Selecting Hash Space
- When the TOTALENTRIES in SYSINDEXSPACESTATS are greater than 10% of TOTALROWS in SYSTABLESPACESTATS.
- When the real-time statistic DATASIZE in SYSTABLESPACESTATS is greater than HASHSPACE in SYSTABLESPACE; maintain HASHSPACE size at least 20% bigger than DATASIZE.
MAXROWS parameter should not be used with Hash.
Also read: New Hash Access Method in DB2