When face such as below questions we can also consider to rebuild primary key.
- Too much index expansion to cause the performance down (IO and CUP cost)
- DB Crash cause the PK data inconsistent.
We can rebuild primary key with following usage:
Rebuild index PRIMARYKEY for t1; //in default DEFTABLESPACE
Rebuild index PRIMARYKEY for t1 in ts1; //support change tablespace only from 5.4 versions