Question

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(For questions 18-20) A database has the following two tables (called A and B): rgio diw and loving A1 A2 A3 A4 B1 B2 B3 RSD PD: | 10 20 30 100 150 400 2 10 40 60 200 250 500 ohod mized orsuqmogu nl 3 30 60 90 300 150 600 om: quo url :8 UIA SA 18. How many fields (Attributes) do tables A and B have; respectively..... annut sini qo12 ou or T8 A. 3,2 B. 3,3 C. 4,3 D. 2,3 E 3,4 oboyob bruxorool: ab: 1000 bus abooob 11:5 19. What is the result of the following SQL statements do: Select A1, A3 A. 1 10 B. 2 40 C. 1 ----20 D. both B & C E. both A&B From A TWO 310 viis les 21909 yi l showion: Where A2 = 10 FOOT Tot 2009 M TOVOS 1 10w soola in zovoo tad shown 20. Write SQL statement to select every record in Table B where B2 is 150. svoda o o onont: A. Select * B. Select B1, B3 C. Select 100, 300 From B From B From B Where B2 = 150 Where B2 = 150 od ol 1 T 01 ol. 2010 soloqol Where B2 = 150 22010A

Answer 1

18. Correct Answer: C. 4,3.

Explanation: Fields (Attributes) mean number of columns in a table. Table A has 4 columns (i.e. A1, A2, A3, A4). Table B has 3 columns (i.e. B1, B2, B3). Thus, option C is the correct answer (i.e. 4,3).

19. Correct Answer: C. 1----20.

Explanation: Lets break the SQL statement and analyse.

(Select A1, A3) --> This is used to fetch columns A1 and A3 from the table.

(From A) --> The Table from which the records are to be fetched. In this case, it is Table A.

(Where A2 = 10) --> Condition part of the statement. This tells us to fetch the data from Table where A2 value is 10.

Hence, (Select A1, A3 From A Where A2 = 10) is used to fetch columns A1=1 and A3=20 from Table A where A2 value is 10. Therefore, the correct answer option is C (i.e. 1----20).

20. Correct Answer: A. Select * From B Where B2 = 150.

Explanation: Lets break the SQL statement and analyse.

(Select *) --> This is used to fetch all the columns from the table.

(From B) --> The Table from which the records are to be fetched. In this case, it is Table B.

(Where B2 = 150) --> Condition part of the statement. This tells us to fetch the data from Table where B2 value is 150.

Hence, (Select * From B Where B2 = 150) is used to fetch all the records from Table B where B2 value is 150. Therefore, the correct answer option is A.