单项选择题
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
相关考题
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多项选择题
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. -
单项选择题
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 -
单项选择题
You have two tables with referential integrity enforced between them. You need to insert data to thechild table first because it is going to be a long transaction and data for the parent table will be available ina later stage， which can be inserted as part of the same transaction. View the Exhibit to examine the commands used to create tables. Which action would you take to delay the referential integrity checking until the end of the transaction（）
A.Set the constraint to deferred before starting the transaction.
B.Alter the constraint to NOVALIDATE state before starting the transaction.
C.Enable the resumable mode for the session before starting the transaction.
D.Set the COMMIT_WAIT parameter to FORCE_WAIT for the session before starting the transaction.
