We have a database file with ten million pages (N = 10,000,000 pages), and we want to sort it using external merge sort. Assume that the DBMS uses quicksort for in- memory sorting. Let B denote the number of buffers. What is the smallest number of buffers B that the DBMS can sort the target file using only four passes?

Q4. Suppose we have the following relations: R(A,B,C) and S(D,E,F). Assume that R uses 500 blocks on disk, and S uses 6,000 blocks. Assume that you got the best possible hash function and there are no overflows for the hash. Assuming that there are 102 blocks of memory space for query processing, what is the least cost (in terms of disk block IOs) for partition hash join for the query R JOINC=D S?

Consider a file with a secondary dense index structure on a non-ordering key field where 120,000 records stored on a disk with block size of 2048 bytes. Length of every record is of fixed and un-spanned. Record size is 150 bytes. Also consider, every record of index file is 20 bytes long. Now assume every block access requires 0.015 second. Can you measure the average improvement in time?

Consider the block size (B) = 512 bytes for the student information table. A file has 40000 employee records of fixed length. Each record has the following fields:Name (50 bytes) SID (10 bytes) and address (41 bytes). Assume that unspanned organization is used to store records and SID takes block pointer 6 bytes. Suppose that the file is ordered by the key field SID and we want to construct a primary index ( sparse) on SID. Calculate the record size R in bytes and find the number of block access required to retrieve a record from the file using binary search

Given B+-tree with height of two (two levels of internal nodes plus a level of leaf nodes).  The order of each internal node is 40 and the order of each leaf node is 36.  On the average, each node is 75% full.  How many disk blocks are currently used for the given B+-tree index? How many records are being stored in the data file which is covered by the given B+-tree?

Suppose a file with 65536 records is organized using multi-level indexing as the file is ordered on a non-key field. Each record is 48 bytes long and the size of its key field is 4 bytes. The indexing is built on the key field of the file. The size of the disk block is 2 KB, and the block pointer size is 12 bytes. The file organization is unspanned. How many blocks will be required for the inner and outer index respectively in a multi-level index? 512 and 2 b) 512 and 4 e) 1024 and 4 d) 1024 and 8

For Heap File with a page directory, assume that a page can contain up to 100 directory entries and a page can contain 1000 records, for a file of 1,000,000 records, what is the number of pages to store these records, assuming that on average data pages are filled up 70%? With this data page utilization, what is the number of pages to store the directory, assuming that each directory page is full? Assuming both the directory and the file are stored on disk, what is the I/O cost to insert one record in worst case, and in the average case?

The CSM Tech organization has a substantial web presence with several publicly accessible web and application servers. You have DNS servers that handle Internet queries for all your publicly accessible resources. However, after doing some statistics analysis on your public DNS servers, you find that your servers are handling recursive lookups for clients that are not within your organization. Your public DNS servers should handle recursive queries only for your internal clients, but the servers should handle iterative (nonrecursive) queries from external sources. What do you recommend? What are the commands needed to implement the solution?

Problem 7 1. Find a recurrence relation for the number of bit strings of length n that contain three consecutive Os. 2. What are the initial conditions? 3. How many bit strings of length seven contain three consecutive Os?