Database Questions and Answers – Transformation of Relational Expressions

This set of Database Multiple Choice Questions & Answers (MCQs) focuses on “Transformation of Relational Expressions”.

1. Consider the following relational schemes for a library database:

Book (Title, Author, Catalog_no, Publisher, YEAR, Price)
Collection (Title, Author, Catalog_no)
WITH the following functional dependencies:
I. Title Author -> Catalog_no
II. Catalog_no -> Title Author Publisher YEAR
III. Publisher Title YEAR -> Price

Assume {Author, Title} is the key for both schemes. Which of the following statements is true?
a) Both Book and Collection are in BCNF
b) Both Book and Collection are in 3NF only
c) Book is in 2NF and Collection is in 3NF
d) Both Book and Collection are in 2NF only
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2. Let R(A,B,C,D,E,P,G) be a relational schema in which the following FDs are known to hold:

AB->CD
DE->P
C->E
P->C
B->G

The relation schema R is
a) in BCNF
b) in 3NF, but not in BCNF
c) in 2NF, but not in 3NF
d) not in 2NF
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3. Which of the following is/are false for RAW mode of FOR XML?
a) XMLSCHEMA option does not returns an in-line XSD schema
b) BINARY BASE32 returns the binary data in base32-encoded format
c) Each row in the query result is transformed into an XML element
d) None of the mentioned
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4. ___________ refers to the ability of the system to recover committed transaction updates if either the system or the storage media fails.
a) Isolation
b) Atomicity
c) Consistency
d) Durability
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5. Which utilities can we use to export data from sql server to a text file?
a) DTS export wizard
b) BCP
c) ISQL
d) DTS export wizard and BCP
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6. You have a column that will only contain values from 0 to 256. What is the most economical data type to use for the column?
a) TINYINT
b) SMALLINT
c) INT
d) DECIMAL(1)
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7. Problems occurs if we don’t implement a proper locking strategy
a) Dirty reads
b) Phantom reads
c) Lost updates
d) Unrepeatable reads
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8. Which of the following fixed database roles can add or remove user IDs?
a) db_accessadmin
b) db_securityadmin
c) db_setupadmin
d) db_sysadmin
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9. By default sql server has ___________ isolation level
a) READ COMMITTED
b) READ UNCOMMITTED
c) SERIALIZABLE
d) REPEATABLE READ
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10. Which of the following pair of regular expression are not equivalent?
a) 1(01)* and (10)*1
b) x(xx)* and (xx)*x
c) (ab)* and a*b*
d) x+ and x*x+
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Sanfoundry Global Education & Learning Series – Database Management System.