how u know when to use a static cache and dynamic cache in
lookup transformation.
- 9 Answers
- 25727 Views
- Accenture, I also Faced
- E-Mail Answers
Answers were Sorted based on User's Feedback
Answer / neetu arora
Dynamic cache is generally used when u are applying lookup
on a target table and in one flow same data is coming twice
for insertion or once for insertion and once for updation.
Performance: dynamic cache decreases the performance in
comparision to static cache since it first looks in the
whole table tht whether data ws previously present if no
thn only it inserts so it takes much tym
Static cache do not see such things just insert data as
many tyms as it is coming.
| Is This Answer Correct ? | 21 Yes | 1 No |
Answer / hari
By default lookup is static.
Dynamic is used whn the records coming frm the source to
target in multiple times. i.e if
1)
emp_id=101...city=hyd...age=25...
(first this is inserted to target)
2)at second time when 101 employee is changing his city frm
hyd to chennai here we need to update the target table with
city name as chennai. thn how lookup cache knows tht a
record is updated...
3) if it is static lookup, after updating tht record it
will not refresh the lookup cache.... where as if it is
dynamic cache it will refresh the cache....
4) Based on our requirement we r going to use.....
| Is This Answer Correct ? | 15 Yes | 1 No |
Answer / krishna
hi neetu,
i hope you were a bit wrong.
static cache is also used to check whether row exists or
not.....
well krishna for your question on dynamic cache..
static cache is one in which data when changed in the
target table cannot be incorporated in the look up on the
fly.
when you use a dynamic cache any changes to the target
table gets reflected in the lookup even if the record is
being inserted or updated in the same mapping run priorly
| Is This Answer Correct ? | 13 Yes | 0 No |
Answer / 24/12/2007
if you need the source data after look up transformation to
transfer any other transformation more than once you can use
dynamic cache otherwise use static cache
| Is This Answer Correct ? | 8 Yes | 4 No |
Answer / nisith
Dear,
Whenever you required changes in your target as a lookup
than go for dynamic.Static means its a readonly why do u
want your server to busy..so stick on static only
comparison is there thats it....
| Is This Answer Correct ? | 1 Yes | 1 No |
Answer / nitin
I have a major doubt in static and dynamic cache.
1. what is the use of both?
2. while using dynamic cache(looking up target table),say a record is entering from source emp_id = 101, which is already in the target so this will be updated am i correct?
3. while using a static cache, same scenario as above the record also gets updated.
4. what happens in both the caches, when again a same record enters from the source
5. when will the record be rejected as a duplicate?
from my understanding, while using a static cache for already existing record in target. when a same record appears twice from source then the record that is appearing second time will be rejected as a duplicate. but in dyanmic cache it will not?.. is this true?
Please help me understand when the record will be rejected as a duplicate and when it will be updated, in case of dynamic and static cache
| Is This Answer Correct ? | 0 Yes | 0 No |
Answer / kareem
Here no one is understanding the question properly,In which
scenario we will go for static or dynamic lookup cache?
| Is This Answer Correct ? | 0 Yes | 1 No |
Answer / amit
when we use conneted type of lookup then we use dynamic
caches& when we use unconncted lookup in the modelling we
use static cache
| Is This Answer Correct ? | 2 Yes | 10 No |
Answer / abhsihek
Hi neetu,
as i know that dynamic lookup alway increase the perfomence
compratively static cache if i am wrong please let me know.
| Is This Answer Correct ? | 0 Yes | 8 No |
What is deployemnt groups, Lables, query and dynamic deployment group.
What is the difference between informatica 8.x and 9.x
what is the size ur source like(file system or database)? how many record daily come u r banking project?
0 Answers Cognizant, Flextronics,
What is the scenario which compels informatica server to reject files?
i had a source containing business,sales,details column and i have to load it to a target but i have some bad records in it , but i have to load 70% of business records and 50% of sales and 95% of details records excluding bad records to achieve this what should be done and what all logic and tx should be used can anyone help? thanks in advance
What is standalone command task?
In a sequential batch can u run the session if previous session fails?
Session S1, S2, and S3. In the session S3 I want to load every Saturday. How it is possible?
differences between service based and product based?
What is the target load order?
What is a configuration management?
in reporting we add some new objects,how we get the count of the newly added objects to the report
Teradata 
