单项选择题

Examine the data from the ORDERS and CUSTOMERS tables. ……

Examine the data from the ORDERS and CUSTOMERS tables.

Evaluate the SQL statement:

What is the result when the query is executed?（）

A.
B.
C.
D. The query fails because the subquery returns more than one row.
E. The query fails because the outer query and the inner query are using different tables.

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单项选择题Which view should a user query to display the columns associated with the constraints on a table owned by the user?（）

A. USER_CONSTRAINTS
B. USER_OBJECTS
C. ALL_CONSTRAINTS
D. USER_CONS_COLUMNS
E. USER_COLUMNS

单项选择题The user Alice wants to grant all users query privileges on her DEPT table. Which SQL statement accomplishes this?（）

A. GRANT select ON dept TO ALL_ USER;
B. GRANT select ON dept TO ALL;
C. GRANT QUERY ON dept TO ALL_USERS
D. GRANT select ON dept TO PUBLIC;

单项选择题Examine the structure of the EMPLOYEES table: EMPLOYEE_ID NUMBER NOT NULL EMP_NAME VARCHAR2(30) JOB_ID VARCHAR2(20) SAL NUMBER MGR_ID NUMBER DEPARTMENT_ID NUMBER You want to create a SQL script file that contains an INSERT statement. When the script is run, the INSERT statement should insert a row with the specified values into the EMPLOYEES table. The INSERT statement should pass values to the table columns as specified below: EMPLOYEE_ID: Next value from the sequence EMP_ID_SEQEMP_NAME and JOB_ID: As specified by the user during run time, through substitution variables SAL: 2000 MGR_ID: No value DEPARTMENT_ID: Supplied by the user during run time through substitution variable. The INSERT statement should fail if the user supplies a value other than 20 or 50. Which INSERT statement meets the above requirements?（）

A. INSERT INTO employees VALUES (emp_id_seq.NEXTVAL, &ename','&jobid', 2000, NULL, &did);
B. INSERT INTO employees VALUES (emp_id_seq.NEXTVAL, '&ename', '&jobid', 2000, NULL, &did IN (20,50));
C. INSERT INTO (SELECT * FROM employees WHERE department_id IN (20,50)) VALUES (emp_id_seq.NEXTVAL, &ename','&jobid', 2000, NULL, &did);
D. INSERT INTO (SELECT * FROM employees WHERE department_id IN (20,50) WITH CHECK OPTION) VALUES (emp_id_seq.NEXTVAL, &ename','&jobid', 2000, NULL, &did);
E. INSERT INTO (SELECT * FROM employees WHERE (department_id = 20 AND department_id = 50) WITH CHECK OPTION ) VALUES (emp_id_seq.NEXTVAL, &ename','&jobid', 2000, NULL, &did);

单项选择题Which constraint can be defined only at the column level?（）

A. UNIQUE
B. NOT NULL
C. CHECK
D. PRIMARY KEY
E. FOREIGN KEY

多项选择题In which two cases would you use an outer join?（）

A. The tables being joined have NOT NULL columns.
B. The tables being joined have only matched data.
C. The columns being joined have NULL values.
D. The tables being joined have only unmatched data.
E. The tables being joined have both matched and unmatched data.
F. Only when the tables have a primary key/foreign key relationship.