Indexing
Question 1 |
There are 5 records in a database.
There is an index file associated with this and it contain the values 1, 3, 2, 5 and 4. Which one of the fields is the index built form?
Age | |
Name | |
Occupation | |
Category |
Question 1 Explanation:
Indexing will be on occupation field because occupation field lexigraphically sorted will give the sequence 1, 3, 2, 5, 4.
Question 2 |
A data consisting of 1,50,000 student-records is stored on a hard disk with block size of 4096 bytes. The data file is sorted on the primary key RollNo. The size of a record pointer for this disk is 7 bytes. Each student-record has a candidate key attribute called ANum of size 12 bytes. Suppose an index file with records consisting of two fields, ANum value and the record pointer to the corresponding student record, is built and stored on the same disk. Assume that the records of data file and index file are not split across disk blocks. The number of blocks in the index file is ______.
698 |
Question 2 Explanation:
Total no. of records = 150000
Block size = 4096 bytes
Key size = 12 bytes
Record pointer size = 7 bytes
Question 3 |
For secondary key processing which of the following file organizations is preferred? Give a one line justification:
Indexed sequential file organization. | |
Two-way linked list. | |
Inverted file organization. | |
Sequential file organization. |
Question 3 Explanation:
Inverted file organization, because of reasons are as follows:
→ An index for each secondary key.
→ An index entry for each distinct value of the secondary key.
→ Exhibits better enquiry performance.
→ An index for each secondary key.
→ An index entry for each distinct value of the secondary key.
→ Exhibits better enquiry performance.
There are 3 questions to complete.