Test: File Structures- 1 - Computer Science Engineering (CSE) MCQ

Contiguous allocation scheme would work best for a file system implementation on a device that can only be accessed sequentially, a tape drive.

• Anchor block contains first records of chain, while overflow block contains records other than those that are 1st records of a chain.
• Anchor record is first record of a block.

Primary indices search key defines the sequential order of fill while secondary indices search key defines an order different from sequential order of fills.

Most database systems use indexes built on some form of a B⁺ tree due to its many advantages, in particular its support for range queries. Leaf nodes are linked together in B* trees hence range queries are faster.

Size of child pointer = 6 byte
Size of search field value takes 14 bytes Block size = 512 

Suppose all nodes are completely full that means every node has n - 1 keys.
Tree has 4 levels. If a new key is inserted then at every level new node will be created.
In worst case root node will also be broken into two parts and we have 4 levels.
So answer should be 5 because tree will be increased with one more level.

From the structure of B⁺ tree we can get the following equation:

In B⁺ tree, non leaf node has no record pointer: (by putting q = 0) 

Largest possible order of a non-leaf node = 34.

In B⁺ tree index method records are physically stored in primary key order.

For storing the records no. of blocks required =n/3
and For storing the keys in dense index no. of blocks required =n/10
So total blocks required 

B⁺ tree is best suitable for sequential acess of data.