database freezing on alter commands..

[bberg@rtnyc.com]

I am trying to run: ALTER table BUSINESS_DIM disable constraint BUSINESS_DIM_FK1


or a refresh on a meterialized view... both statements simply hang and freeze... update, insert statements work for the most part...
there is nothing in the alert log, and no locks in v$lock.

how I can I determine what is preventing the freeze?

p.s. I restarted the instance, and it worked... then a few minutes later it stopped working.

[tamilselvan]

Probably the index may be corrupt. Try to drop FK and index, then later recreating it. If the database is freezed even after the FK is dropped, then the problem may be somewhere else.