Question 1 :
The relational scheme Scholar Management(name, courseNo, rollNo, grade) has the following functional dependencies :
name, courseNo -> grade
rollNo, courseNo -> grade
name ->rollNo
rollNo -> name
The highest normal form of this relational scheme is
Options :
a. 1NF
b. 2NF
c. 3NF
d. BCNF
Answers :
c. 3NF
Question 2 :
An irreversible error in a database system can be caused by :
Options :
a. A transaction writes a data item after it is read by an uncommitted transaction
b. A transaction writes a data item after it is written by an uncommitted transaction
c. All of the above
d. None of the above
Answers :
b. A transaction writes a data item after it is written by an uncommitted transaction
Question 3 :
The table itemMaster(item,cost) holds the item name and the respective cost of the item .If there all the items are having different cost, then what does the SQL query do :
Select item
fromitemMaster as B
where (select count(*)
fromitemMaster as T
whereT.cost>B.cost)<5
Options :
a. Displays the 5th most costly item
b. Displays the 5th most cheapest item
c. Displays the 4 most costly items
d. Displays the 5 most costly items
Answers :
d. Displays the 5 most costly items
Question 4 :
State TRUE or FALSE
Every relation in BCNF is also in 3NF
Options :
a. TRUE
b. FALSE
Answers :
a. TRUE
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