We are here with you hands in hands to facilitate your learning & don't appreciate the idea of copying or replicating solutions. Read More>>
+ Link For Assignments, GDBs & Online Quizzes Solution
+ Link For Past Papers, Solved MCQs, Short Notes & More
Dear Students! Share your Assignments / GDBs / Quizzes files as you receive in your LMS, So it can be discussed/solved timely. Add Discussion
How to Add New Discussion in Study Group ? Step By Step Guide Click Here.
Graded Discussion Board (GDB)
Data Warehousing (CS614)
GDB of the subject Data Warehousing (CS614) is going to open in a couple of days. Before submitting the GDB, please read all instructions thoroughly.
The GDB will remain open for two days (48 hours).
You may submit your GDB from “August 2, 2018 To August 3, 2018, 11:59 PM”.
The task of optimizer is to decide which join technique should be used for a particular search query. In a decision support system, Sort Merge Join and Hash Based join are some important join techniques which can be used by the optimizer. Discuss some factors on the basis of which optimizer can decide to use either Sort Merge Join or Hash based Join.
Note: A concise, coherent and to the point comment is preferred over lengthy comment having irrelevant details. Comments, posted on regular Lesson's MDB or sent through email will NOT be considered in any case. For any queries please email at CS614@vu.edu.pk
Best of Luck!
.+ http://bit.ly/vucodes (Link for Assignments, GDBs & Online Quizzes Solution)
+ http://bit.ly/papersvu (Link for Past Papers, Solved MCQs, Short Notes & More)+ Click Here to Search (Looking For something at vustudents.ning.com?) + Click Here To Join (Our facebook study Group)
A hash join is performed by hashing one informational index into memory in light of join sections and perusing the other one and testing the hash table for matches. The hash join is minimal effort when the hash table can be held completely in memory, with the aggregate cost adding up to next to no more than the cost of perusing the informational collections. The cost rises if the hash table must be spilled to plate in a one-pass sort, and rises significantly for a multi pass sort
read the question again
Discuss some factors on the basis of which optimizer can decide to use either Sort Merge Join or Hash based Join.
optimizer will use merge join when data is sorted and hash join when data is not sorted.