when will we go for unconnected lookup transformation in
Informatica?
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Answer / suneelkumar.dasari
If u want to use the same look up T/R more than one time,you should use compulsory Unconnected lookup.A common use for unconnected Lookup transformations is to update slowly changing dimension tables.I know these 2 uses.
| Is This Answer Correct ? | 15 Yes | 0 No |
Answer / balu
above cases as well as if you want to get single port from
the lookup table then you should go for unconnected lookup
transformation.
| Is This Answer Correct ? | 7 Yes | 0 No |
Answer / g. manthiramoorthy
1. Calling the same lookup multiple times in one mapping
2. Testing the results of a lookup in an expression
3. Filtering rows based on the lookup results
4. Marking rows for update based on the result of a lookup,
such as updating slowly changing dimension tables
| Is This Answer Correct ? | 6 Yes | 0 No |
Answer / naresh
If we want to use multiple times in same mapping you can go
for un-connected lookup and It depends on how much data
your processing.
performance wise unconnected lookup is better because its
like reusable one and it will lookup the values only the
condition meet the criteria.
1. It will return only one value
2. It will act as static cache
| Is This Answer Correct ? | 3 Yes | 0 No |
Answer / kamesh
The main advantage of using an unconnected lookup is the fact that you can use it in an expression/any other transformation like a “function” in other programming languages. The Lookup Cache is calculated only once as part of the session initialization and hence more efficient, since all subsequent look-ups will re-use the Cache.
| Is This Answer Correct ? | 1 Yes | 0 No |
Answer / nag
To retrieve the data dynamically. And it is used for other
transformations in the same mapping.
| Is This Answer Correct ? | 1 Yes | 12 No |
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