Solution Library

Estimation of I/Os  Cost for Join Algorithm

Question

Consider the join R 1R:a=S:b S of relations R and S with the following information.

R has 10,000 tuples and a blocking factor of 10.

S has 2,000 tuples and a blocking factor of 10.

S.b is the primary key of S.

Both R and S are stored in simple heap files and neither relation has any index.

Up to 52 buffer frames available.

For each of the three join algorithms: (a) Blocked nested-loop join, (b) Sort-merge join, and

(c) Hash join, answer the following questions. Unless stated otherwise, the join cost should

be the number of page I/Os excluding the cost for writing the join result.

(a) Estimate the I/O cost and the number of buffer frames that is needed to obtain that cost.

(b) What is the best cost of the join algorithm if additional buffer is available? How many

buffer frames are required to obtain that cost?

(c) How many blocks does the join result contain?

(d) If R:a is a foreign key referencing S:b, how would the answers to the previous questions

change?

Summary

This question belongs to computer science and discusses about join cost for three algorithms.

Word count: NA

 

Download Full Solution

Comments

  • HWA
    Rasha

    this is a very good website

  • HWA
    maani

    I have 50 questions for the same test your page is showing only 28

  • HWA
    joeanne

    hi can you please help or guide me to answer my assignments. thanks

  • HWA
    joeanne

    hi can anyone help or guide me to my assignments. thanks

  • HWA
    Monik


  • HWA
    Cristina

    This solution is perfect ...thanks

  • HWA
    Janete

    Hello Allison,I love the 2nd image that you did! I also, had never heard of SumoPaint, is something that I will have to exolpre a bit! I understand completely the 52 (or so) youtube videos that you probably watched. Sometimes they have what you want, sometimes they don't! However, it is always satisfying when you are able to produce something that you have taught yourself. Great job!Debra 0 likes

  • HWA
    Sandeep

    Perfect bank of solution. 

  • HWA
    Oxana

    great !

  • HWA
    Paul Brandon-Fritzius

    thanks for the quick response. the solution looks good. :)

  • HWA
    tina Johnson

    thnx for the answer. it was perfect. just the way i wanted it. 

  • HWA
    Giuseppe

    works fine.