Shulou(Shulou.com)06/01 Report--

1.1 create index

If the target table has a DML operation and is not committed, an error is reported when the index is created

ORA-00054: resource busy and acquire with NOWAIT specifiedor timeout expired

If an index (create index) is being established on the target table, the DML operation will be blocked

Summary: direct create index must determine that the target table has no DML operation, or index is established when the business is out of service.

1.2 create index online

If the target table has a DML operation and is not committed, using online at this time will wait for the commit before indexing

If indexing (create index online) is in progress on the target table, then the DML operation will not be blocked, but if it is not committed, indexing will be blocked all the time. Continue to create the index after the DML commits.

Summary: if the target library is being loaded frequently, consider using online to build it.

In fact, with the contention for resources, that is, the emergence of lock, interested friends can study the compatibility matrix of lock.

Welcome to subscribe "Shulou Technology Information " to get latest news, interesting things and hot topics in the IT industry, and controls the hottest and latest Internet news, technology news and IT industry trends.