Creating an Index Online在线创建索引

You can create and rebuild indexes online. Therefore, you can update base tables at the same time you are building or rebuilding indexes on that table. You can perform DML operations while the index build is taking place, but DDL operations are not allowed. Parallel execution is not supported when creating or rebuilding an index online.

The following statements illustrate online index build operations:

CREATE INDEX emp_name ON emp (mgr, emp1, emp2, emp3) ONLINE;

online方式创建索引，对表创建或编译索引过程中可以对表进行DML操作，但是不允许DDL操作，并且此种方式不支持不行。