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  1. Which of the following query finds the total rating of the sailors who have reserved boat "103"?

  2. A.

     SELECT SUM(s.rating) FROM sailors s, reserves r AND r.bid = 103;

    B.

     SELECT s.rating FROM sailors s, reserves r WHERE s.sid = r.sid AND r.bid = 103

    C.

     c) SELECT COUNT(s.rating) FROM sailors s, reserves r WHERE s.sid = r.sid AND r.bid = 103

    D.

     SELECT SUM(s.rating) FROM sailors s, reserves r WHERE s.sid = r.sid AND r.bid = 103

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  3. The SELECT statement SELECT 'Hi' FROM DUAL WHERE NULL = NULL; Outputs

  4. A.

     Hi

    B.

     FLASE

    C.

     TRUE

    D.

     Nothing

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  5. Which of the following is illegal?

  6. A.

     SELECT SYSDATE - SYSDATE FROM DUAL;

    B.

     SELECT SYSDATE - (SYSDATE - 2) FROM DUAL;

    C.

     SELECT SYSDATE - (SYSDATE + 2) FROM DUAL;

    D.

     None of these

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  7. If a query involves NOT, AND, OR with no parenthesis

  8. A.

     NOT will be evaluated first; AND will be evaluated second; OR will be evaluated last.

    B.

     NOT will be evaluated first; OR will be evaluated second; AND will be evaluated last.

    C.

     AND will be evaluated first; OR will be evaluated second; NOT will be evaluated last.

    D.

     The order of occurrence determines the order of evaluation.

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  9. Let the statement
    SELECT column1 FROM myTable;
    return 10 rows. The statement
    SELECT ALL column1 FROM myTable;
    will return

  10. A.

     less than 10 rows

    B.

     more than 10 rows

    C.

     exactly 10 rows

    D.

     None of these

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  11. Table employee has 10 records. It has a non-NULL SALARY column which is also UNIQUE.
    The SQL statement
    SELECT COUNT(*) FROM employee WHERE SALARY > ALL (SELECT SALARY FROM EMPLOYEE);
    prints

  12. A.

     10

    B.

     9

    C.

     5

    D.

     0

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  13. Which of the following SQL commands can be used to add data to a database table?

  14. A.

     ADD

    B.

     UPDATE

    C.

     APPEND

    D.

     INSERT

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  15. Which of the following join is also called as an 'inner-join'?

  16. A.

     Non-Equijoin

    B.

     Self-Join

    C.

     Equijoin

    D.

     None of these

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  17. Which of the following is NOT a type of SQL constraint?

  18. A.

     PRIMARY KEY

    B.

     ALTERNATE KEY

    C.

     FOREIGN KEY

    D.

     UNIQUE

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  19. What is an SQL virtual table that is constructed from other tables?

  20. A.

     view

    B.

     A relation

    C.

     Just another table

    D.

     Query results

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