單項選擇題

Which statement describes the effect on an index， when the indexed column for the rows is updatedin the base table（）

A.An update in a leaf row takes place.
B.The index becomes invalid after the update.
C.The leaf block containing the row to be updated is marked as invalid.
D.A row in the leaf block of the index for the key value is logically deleted and a new leaf row is inserted

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多項選擇題

The session of user SCOTT receives the following error after executing an UPDATE command onthe EMP table：
ERROR at line 1：
ORA-00060： deadlock detected while waiting for resource
On investigation， you find that a session opened by user JIM has a transaction that caused the deadlock.
two statements are true regarding the session of SCOTT in this scenario（）

A.The session is terminated after receiving the error and JIM can continue with his transaction.
B.SCOTT should perform a COMMIT or ROLLBACK to allow JIM to continue with his transaction.
C.The session is rolled back after receiving the error and JIM can continue with his transaction.
D.SCOTT has to reexecute the last command in the transaction after he commits the transaction.

單項選擇題

The table contains a million rows for zonewise analysis in the DSS system. DML operations areperformed very rarely on the table. You decide to prepare an index on the ZONE column to enhance theperformance of the queries on the ZONE column.
Which type of index would you select in this scenario（）

A.Bitmap index
B.Reverse key index
C.Normal B-Tree index
D.Function-based index

Which statement describes the effect on an index， when the indexed column for the rows is updatedin the base table（）

你可能感興趣的試題

The table contains a million rows for zonewise analysis in the DSS system. DML operations areperformed very rarely on the table. You decide to prepare an index on the ZONE column to enhance theperformance of the queries on the ZONE column. Which type of index would you select in this scenario（）

Which statement describes the effect on an index， when the indexed column for the rows is updatedin the base table（）

The table contains a million rows for zonewise analysis in the DSS system. DML operations areperformed very rarely on the table. You decide to prepare an index on the ZONE column to enhance theperformance of the queries on the ZONE column.
Which type of index would you select in this scenario（）