Chapter 7 (True/False)

Question 1

1. A database language enables the user to create database and table structures to perform basic data management
chores.

Answer

true

Question 2

2. A database language enables the user to perform complex queries designed to transform the raw data into useful
information.

Answer

true

Question 3

3. The ANSI prescribes a standard SQL–the current fully approved version is known as SQL-07.

Answer

true

Question 4

4. The ANSI SQL standards are also accepted by the ISO.

Answer

true

Question 5

5. SQL is considered difficult to learn; its command set has a vocabulary of more than 300 words.

Answer

true

Question 6

6. Data type selection is usually dictated by the nature of the data and by the intended use.

Answer

true

Question 7

7. Only numeric data types can be added and subtracted in SQL.

Answer

true

Question 8

8. Entity integrity is enforced automatically when the primary key is specified in the CREATE TABLE command
sequence.

Answer

true

Question 9

9. The CHECK constraint is used to define a condition for the values that the attribute domain cannot have.

Answer

true

Question 10

10. SQL requires the use of the ADD command to enter data into a table.

Answer

true

Question 11

11. You cannot insert a row containing a null attribute value using SQL

Answer

true

Question 12

12. To list the contents of a table, you must use the DISPLAY command.

Answer

true

Question 13

13. Any changes made to the contents of a table are not physically saved on disk until you use the SAVE<table name> command.

Answer

true

Question 14

14. The COMMIT command does not permanently save all changes. In order to do that, you must use SAVE

Answer

true

Question 15

15. If you have not yet used the COMMIT command to store the changes permanently in the database, you can restore the database to its previous condition with the ROLLBACK command.

Answer

true

Question 16

16. All SQL commands must be issued on a single line

Answer

true

Question 17

17. Although SQL commands can be grouped together on a single line, complex command sequences are best shown on separate lines, with space between the SQL command and the command’s components.

Answer

true

Question 18

18. You can select partial table contents by naming the desired fields and by placing restrictions on the rows to be included in the output.

Answer

true

Question 19

19. Oracle users can use the Access QBE (query by example) query generator.

Answer

true

Question 20

20. Since computers identify all characters by their numeric codes, mathematical operators cannot be used to place restrictions on character-based attributes.

Answer

true

Question 21

21. String comparisons are made from left to right.

Answer

true

Question 22

22. Date procedures are often more software-specific than other SQL procedures.

Answer

true

Question 23

23. SQL allows the use of logical restrictions on its inquiries such as OR, AND, and NOT.

Answer

true

Question 24

24. ANSI-standard SQL allows the use of special operators in conjunction with the WHERE clause.

Answer

true

Question 25

25. The conditional LIKE must be used in conjunction with wildcard characters.

Answer

true

Question 26

26. Most SQL implementations yield case-insensitive searches.

Answer

true

Question 27

27. Some RDBMSs, such as Microsoft Access, automatically make the necessary conversions to eliminate case
sensitivity.

Answer

true

Question 28

28. The COUNT function is designed to tally the number of non-null "values" of an attribute, and is often used in conjunction with the DISTINCT clause.

Answer

true

Question 29

29. To join tables, simply enumerate the tables in the FROM clause of the SELECT statement. The DBMS will create a Cartesian product of every table in the FROM clause. To get the correct results, you need to select the rows in which the common attributes do not match.

Answer

true

Question 30

30. When joining three or more tables, you need to specify a join condition for one pair of tables.

Answer

true

Chapter 7 (True/False)

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