Using Hash-Join Overflow and DBSPACETEMP

If you do not set the DBSPACETEMP environment variable and you do not specify a value for the DBSPACETEMP configuration parameter, the optimizer will perform a join or group-by operation with a hash join. The database server will then direct any overflow that results from the join to the root dbspace directory.

To modify the DBSPACETEMP parameter dynamically, use the onutil SET command. Example:

% onutil
1> SET DBSPACETEMP "tmpspace1,tmpspace2,tmpspace3";