单项选择题
Which statement is true regarding Flashback Version Query？（）
A. It returns versions of rows only within a transaction.
B. It can be used in subqueries contained only in a SELECT statement.
C. It will return an error if the undo retention time is less than the lower bound time or SCN specified.
D. It retrieves all versions including the deleted as well as subsequently reinserted versions of the rows.
相关考题
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单项选择题
View the Exhibit and examine the structure of the EMP table. You executed the following command to add a primary key to the EMP table： ALTER TABLE emp ADD CONSTRAINT emp_id_pk PRIMARY KEY （emp_id） USING INDEX emp_id_idx； Which statement is true regarding the effect of the command？（）
A. The PRIMARY KEY is created along with a new index.
B. The PRIMARY KEY is created and it would use an existing unique index.
C. The PRIMARY KEY would be created in a disabled state because it is using an existing index.
D. The statement produces an error because the USING clause is permitted only in the CREATE TABLE command. -
单项选择题
The user SCOTT who is the owner of ORDERS and ORDERJTEMS tables issues the following GRANT command： GRANT ALL ON orders， order_items TO PUBLIC； What correction needs to be done to the above statement？ （）
A. PUBLIC should be replaced with specific usernames.
B. ALL should be replaced with a list of specific privileges.
C. WITH GRANT OPTION should be added to the statement.
D. Separate GRANT statements are required for ORDERS and ORDERJTEMS tables. -
单项选择题
View the Exhibit and examine the data in ORDERS_MASTER and MONTHLYjDRDERS tables. What would be the outcome of the above statement？（）
A. The ORDERS_MASTER table would contain the ORDERJDs 1 and 2.
B. The ORDERS_MASTER table would contain the ORDERJDs 1， 2 and 3.
C. The ORDERS_MASTER table would contain the ORDERJDs 1， 2 and 4.
D. The ORDERS MASTER table would contain the ORDER IDs 1， 2， 3 and 4.
