how lookup is acting as both active and passive ?
how is it possitble?

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how lookup is acting as both active and passive ? how is it possitble?..

Answer / meenal

In Informatica 9.1 Lookup is active because of property - "Lookup policy on multiple match", this can be chosen as first, last, any value or all values. So now we can configure the Lookup transformation to return all rows that match a lookup condition. Hence, a Lookup transformation is an active transformation when it can return more than one row for any given input row.

However this property is available only for connected lookup, unconnected lookups are still passive.

Is This Answer Correct ?    43 Yes 0 No

how lookup is acting as both active and passive ? how is it possitble?..

Answer / surendra kumar

Hi,

Lookup is both "Active" as well as "Passive"

Till informatica 8 it was only passive because one of its property "Lookup Policy on Multiple Match" has options of:
i)any values
ii)first values
iii)last values
iv)report error
So for each input record it will produce one output record either any corresponding matching value or Null. But number of Input row is equal to number of output row.

But from Informatica 9 onwards there is one addition in the option of "Lookup Policy on Multiple Match" is:
"Use All Values"
using this property one input row can give multiple output rows i.e number of input rows is not equal to number of output rows.

Thanks & Regards
Surendra Kumar

Is This Answer Correct ?    39 Yes 0 No

how lookup is acting as both active and passive ? how is it possitble?..

Answer / priyanka

hi
Suppose if we have 3 records with same key value, only then
first, last are considered. Based on given preference, if
it is first, it will consider the record which comes first.
If it is last, it considers the matched record which comes
by the end of that session.If there are no duplicate
records then,if there is a matched record it will return
the respective data for that record else with return NULL.
But, as it tracks all the records with some result i.e
either with its value or NULL, we consider it as passive
transformation

Is This Answer Correct ?    0 Yes 4 No

how lookup is acting as both active and passive ? how is it possitble?..

Answer / vidyasagar

@Srinivas

after condition satisfies it does'nt reduces rows

say

src_table Lookup_table Result
10 10 10
20 Null
30 Null

number of sources=3 and result also 3 rows hence

Lookup is a passive transformation :)

Regards:
Vidyasagar

Is This Answer Correct ?    7 Yes 12 No

how lookup is acting as both active and passive ? how is it possitble?..

Answer / jay

There is an option in the properties of Lookup transformation in which we could select "First", "Any" or "Last" which would may give only one row.

So it is Active transformation.

Is This Answer Correct ?    11 Yes 16 No

how lookup is acting as both active and passive ? how is it possitble?..

Answer / vidyasagar

Dude Jay,

its a passive transformation

in yo case eventhough you are selecting first last or any
it will select the selected column and null for the rest of
the rows so the number of rows remains same , hence its the
passive transformation.

one more thing you can by-pass the lookup so only a passive
txn can be by-passed.

if anyone have any queries lemme know :)

Is This Answer Correct ?    2 Yes 8 No

how lookup is acting as both active and passive ? how is it possitble?..

Answer / nsiddardh

Both connected ans unconnected look-up transformations are
passive.because the input rows supplied to the look-up are
equal to output rows.so we call look-up transformation is
passive.

Is This Answer Correct ?    17 Yes 24 No

how lookup is acting as both active and passive ? how is it possitble?..

Answer / srinivas

hi
experts, i suppose to eswar 's answers
lookup transformation is passive transformation .ie it cant
reduce rows after condition satisfy or nt

Is This Answer Correct ?    3 Yes 11 No

how lookup is acting as both active and passive ? how is it possitble?..

Answer / eswar

Both Lookup transformations are passive

"A passive transformation does not change the number of
rows that pass through it, such as an Expression
transformation that performs a calculation on data and
passes all rows through the transformation."

And

"An active transformation can change the number of rows
that pass through it, such as a Filter transformation that
removes rows that do not meet the filter condition."

Therefore, the Lookup transformations work as passive but
not as active transformations.

Is This Answer Correct ?    7 Yes 26 No

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