Examine the following output:
Which two statements about the above index are true? (Choose two.)
A.
It is ignored by the query optimizer.
B.
It is not used while the index is being rebuilt.
C.
The index cannot be rebuilt, and has to be re-created.
D.
The index is automatically rebuilt when used the next time.
When you make an index unusable, it is ignored by the optimizer and is not maintained by DML. When you make one partition of a partitioned index unusable, the other partitions of the index remain valid.
You must rebuild or drop and re-create an unusable index or index partition before using it.
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