Question

An article in the Journal of Database Management "Experimental Study of a Self-Tuning Algorithm for DBMS Buffer Pools," (2005, Vol. 16, pp. 1-20) provided the workload used in the TPC-C OLTP (Transaction Processing Performance Council's Version C On-Line Transaction Processing) benchmark, which simulates a typical order entry application. Average frequencies and operations in TPC-C Transaction Frequency Selects Updates Inserts Deletes Non-unique Joins Selects New order 43 Payment 44 Order Status 4 5 23 4.2 11.4 130 11 12 3 1 0 0 1200 0 0 0 0.6 0 0.6 100 0 0 0 Delivery Stock Level 4 0 0 0 0 0 The frequency of each type of transaction in the second column) can be used as the percentage of each type of transaction. Let X, Y, and Z denote the average number of selects, updates, and inserts operations required for each type of transaction, respectively. Calculate the following: (c) P(X < 6, Y < 6|Z = 0) = Round your answer to three decimal places (e.g. 98.765). (d) E (X Y = 0, Z=0) = Round your answer to one decimal place (e.g. 98.7).

Answer 1

c)P (X<6 ,Y<6|Z=0) =4/(4+5+4)=0.308 (for z=0, there are bottom 3 rows are correct in whcih last one has x<6 and y<6)

d) E(X|Y=0,Z=0)= $\sum$ x*P(x|y=0,z=0)= 11.4*(4/8)+0*(4/8)=5.7