Scenario5

Source              
Col_1    Col_2       
D1       A1          
D1       A2          
D2       A3         
D2       A4           

D2       A5           

D3       A6           
D3       A7 

Target 
Col_1    Col_2   
D1     A1-A2 
D2    A3-A4-A5 
D3     A6-A7


Answer :

The Following can be obtained by using a Sorter transformation , Expression transformation and a aggregator transformation.

Let me show the mapping now.,

This shows the mapping for the above scenario.
Now lets see them in detail
1) Usual Sorter on Col1
2) Expression t/f like below

3) Aggregator t/f as below

How will you approach this : 2

Input :

Student Name	Maths	Life Science	Physical Science
Sam	100	70	80
John	75	100	85
Tom	80	100	85

Output :

Student Name	Subject Name	Marks/Avg Marks
Sam	Maths	100/85
Sam	Life Science	70/90
Sam	Physical Science	80/83.33
John	Maths	75/85
John	Life Science	100/90
John	Physical Science	85/83.33
Tom	Maths	80/85
Tom	Life Science	100/90
Tom	Physical Science	85/83.33

Aggregating without using Aggregator Transformation

In informatica level the aggregator transformations output can be obtained by replacing it with the following transformations

1) Sorter transformation -- Used to sort the data asc/dec

2) Expression Transformation -- basic transformation used almost in all the mappings

3) Filter Transformation -- To obtain the records with specific condn.

Aggregator transformation will reduce the number of records by aggregating on some specific columns given by us .

The Reverse transformation of Aggregator is Normalizer Transformation which will increase the number of Records.