Difference in the implementation of lookup and join
stages,in joining two tables?
Answer Posted / zulfi123786
Hi This is Zulfi
Basically Join is used when you have large amount of data
about in millions and it performs inner join,left
outer,right outer and full outer joins
The join stage requires the incomming data to be hash
partitioned and sorted on the joining keys
The look up is used when the reference records are fewer in
number about less than one lakh and it doesnot require the
incomming source data to be sorted, instead the refrence
link should be in Entire partition mode.
In look up there are two types
Normal and Sparse
Sparse is available only when the reference is a database.
usually Normal has to be used unless when the refrence to
source rows ratio is 100:1
| Is This Answer Correct ? | 8 Yes | 0 No |
Post New Answer View All Answers
What are the steps required to kill the job in Datastage?
Can you define merge?
How to clean the datastage repository?
Differentiate between Symmetric Multiprocessing and Massive Parallel Processing?
How do you remove duplicate values in datastage?
How do you register plug-ins?
Define Merge?
Explain connectivity between datastage with datasources?
1.what is repartionoing technique? 2.what deliverables transferred to client using datastage? 3.how to write loop statements using nested loop sequence?
What are the difference types of stages?
Which is the best institute in Hyderabad to learn OBIEE and DataStage?Please tell me faculty name also
In a batch if a job fails in between and you want to restart the batch from that particular job and not from the scratch then what will you do?
How do you start developing a datastage project?
What all the types of jobs you developed?
What is the precedence of stage variables,derivations, and constraints?