Friday, November 28, 2014

Physical Database Design

1. 
If a denormalization situation exists with a one-to-one binary relationship, which of the following is true?
A.All fields are stored in one relation.
B.All fields are stored in two relations.
C.All fields are stored in three relations.
D.All fields are stored in four relations.

2. 
Selecting a data type involves which of the following?
A.Maximize storage space
B.Represent most values
C.Improve data integrity
D.All of the above.
3. 
What is the best data type definition for Oracle when a field is alphanumeric and has a length that can vary?
A.VARCHAR2B.CHAR
C.LONGD.NUMBER
4. 
If a denormalization situation exists with a many-to-many or associative binary relationship, which of the following is true?
A.All fields are stored in one relation.
B.All fields are stored in two relations.
C.All fields are stored in three relations.
D.All fields are stored in four relations.
5. 
Which of the following is an advantage of partitioning?
A.Complexity
B.Inconsistent access speed
C.Extra space
D.Security
6. 
The blocking factor is:
A.a group of fields stored in adjacent memory.
B.the number of physical records per page.
C.attributes grouped together by the same primary key.
D.attributes grouped together by the same secondary key.
7. 
Which of the following improves a query's processing time?
A.Write complex queries.
B.Combine a table with itself.
C.Query one query within another.
D.Use compatible data types.
8. 
Which of the following are integrity controls that a DBMS may support?
A.Assume a default value in a field unless a user enters a value for that field.
B.Limit the set of permissible values that a field may assume.
C.Limit the use of null values in some fields.
D.All of the above.
9. 
Which of the following is not a factor to consider when switching from small to large block size?
A.The length of all of the fields in a table row.
B.The number of columns
C.Block contention
D.Random row access speed
10. 
What is the best data type definition for Oracle when a field is alphanumeric and has a fixed length?
A.VARCHAR2B.CHAR
C.LONGD.NUMBER

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