Oracle 1z0-071 問題集

質問 1：
You execute this command:
ALTER TABLE employees SET UNUSED (department_id);
Which two are true?
A. The DEPARTMENT_ID column can be recovered from the recycle bin
B. No updates can be made to the data in the DEPARTMENT_ID column.
C. The DEPARTMENT_ID column is set to null for all tows in the table
D. The storage space occupied by the DEPARTMENT_ID column is released only after a COMMIT is issued.
E. A new column with the name DEPARTMENT_ID can be added to the EMPLOYEES table.
F. A query can display data from the DEPARTMENT_ID column.
正解：B,E

質問 2：
Which three actions can you perform on an existing table containing date?
A. Change a DATE Column containing data to a NUMBER data type.
B. Add a new NOT NULL Column with a DEFAULT value.
C. Increase the width of a numeric column.
D. Add a new column as the table's first column.
E. Change the default value of a column.
F. Define a default value that is automatically inserted into a column containing nulls.
正解：B,C,E

質問 3：
Which two queries execute successfully?
A. select INTERVAL '1' DAY +INTERVAL '1' MONTH FROM DUAL;
B. SELECT INTERVAL '1' DAY - SYSDATE FROM DUAL;
C. SELECT INTERVAL '1' DAY - INTERVAL '1' MINUTE FROM DUAL;
D. SELECT SYSTIMESTAMP + INTERVAL '1' DAY FROM DUAL;
E. SELECT SYSDATE "INTERRVAL '1' DAY FROM DUAL;
正解：C,D

質問 4：
which three statements are true about indexes and their administration in an Oracle database?
A. A DESCENDING INDEX IS A type of function-based index
B. The same table column can be part of a unique and non-unique index
C. AN INDEX CAN BE CREATED AS part of a CREATE TABLE statement
D. AN INVISIBLE INDEX is not maintained when DML is performed on its underlying table.
E. A DROP INDEX statement always prevents updates to the table during the drop operation
F. IF a query filters on an indexed column then it will always be used during execution of query
正解：A,C,E

質問 5：
Which two are true about queries using set operators (UNION, UNION ALL, INTERSECT and MINUS)?
A. None of the set operators can be used when selecting CLOB columns.
B. There must be an equal number of columns in each SELECT list.
C. The FOR UPDATE clause cannot be specified.
D. The name of each column in the first SELECT list must match the name of the corresponding column in each subsequent SELECT list.
E. Each SELECT statement in the query can have an ORDER BY clause.
正解：B,C

質問 6：
Examine the data in the PRODUCTS table:

Examine these queries:
1. SELECT prod name, prod list
FROM products
WHERE prod 1ist NOT IN(1020) AND category _id=1;
2. SELECT prod name, | prod _ list
FROM products
WHERE prod list < > ANY (1020) AND category _id= 1;
SELECT prod name, prod _ list
FROM products
WHERE prod_ list <> ALL (10 20) AND category _ id= 1;
Which queries generate the same output?
A. 1, 2 and 3
B. 1 and 2
C. 2 and 3
D. 1 and 3
正解：D

質問 7：
Which two are true about global temporary tables?
A. Their data is always stored in the default temporary tablespace of the user who created them.
B. They can be created only by a user with the DBA role,but can be accessed by all users who can create a session.
C. If the ON COMMIT clause Is transaction-specific, all rows in the table are deleted alter each COMMIT or ROLLBACK.
D. Indexes can be created on them.
E. Backup and recovery operations are available for these tables.
F. If the ON COMMIT clause is session-specific,the table is dropped when the session is terminated.
正解：C,F

質問 8：
You execute this command:
TRUNCATE TABIE depts;
Which two are true?
A. A FLASHBACK TABLE statement can be used to retrieve the deleted data.
B. It retains the indexes defined on the table.
C. It drops any triggers defined on the table.
D. It always retains the space used by the removed rows.
E. It retains the integrity constraints defined on the table,
F. A ROLLBACK statement can be used to retrieve the deleted data.
正解：B,E

質問 9：
Which two statements are true about truncate and delete?
A. the result of a truncate can be undone by issuing a ROLLBACK.
B. truncate leavers any indexes on the table in an UNUSABLE STATE.
C. TRUNCATE can use a where clause to determine which row(s) should be removed.
D. the result of a delete can be undone by issuing a rollback
E. delete can use a where clause to determine which row(s) should be removed.
正解：D,E