MCA 1103
2266-I/01

M.C.A. DEGREE EXAMINATION - 2001

First Year - First Semester
FILE STRUCTURES

(Effective from the Admitted Batch of 2000 - 2001)

Time: Three hours
Maximum: 75 marks

First question is compulsory.
Answer any FOUR from the Remaining.
All questions carry equal marks.
Write all Parts of any question at one place.,

1. a. Difference between logical record and physical record (2)

b) Whit is redundancy reduction. (2)

c) What is an Index. (2)

d) Write B-tree properties. (2)

e) What is fragmentation. (2)

f) What is Data Compression. (2)

g) Distinguish between- file access and file organisation (3)

2. a Explain about Internal and External fragmentation.

b. Explain about Inverted files.

3. a. Explain briefly about, buffer Management.

b. A given disc ahs 512 bytes in each sector, 11 surfaces on which to record information, 200 tracks per surface and 20 sectors on each track.

i. What is the total capacity of the disc in. megabytes.

ii. How many 120-byte logical records can be stored on 10 cylinders of this disc, if we assume, that no logical record is split across a sector boundaries.

4. a Explain about Indexed sequential file organisation.

b. How do you retrieve special subset of records from a data file Using combination. of secondary keys.

5. How do you maintain simple prefix b++ tree with the following assumptions.

a. Changes localized to single blocks in the sequence set.

b. Changes involving multiple blocks in the set.

6. a. Explain why the number of comparisons is not adequate ate for measuring performance in sorting large files.

b. Construct a B-tree for the set of key values that fit in a one node is 5. Show the steps involved in the following tasks.

i. Find record with key 10
ii. Insert 42
iii. Delete 44

7. (a) What is Hashing? Explain about Hashing functions.

(b) Write simple hashing algorithms.

8. (a) Explain about Extendable Hashing.

(b) How to design File Structure for CD-ROM.