✍ Kashif M
Trends

Monday, 28 September 2015

Expression Transformation Interview Question ( Part - 1)



What is an Expression Transform?

Answer:

Expression is a Passive connected transformation used to calculate values in a single row before you write to the target. We can use the Expression transformation to perform any non-aggregate calculations. We can al-so use the Expression transformation to test conditional statements before you output the results to target tables or other transformations.

For example, we might need to adjust employee salaries, concatenate first and last names, or convert strings to numbers.

Expression Transformation Interview Question
Expression Transformation Interview Question

How many types of ports are there in Expression transform?

Answer:

There are three types of ports- INPUT, OUTPUT, and VARIABLE

What is the execution order of the ports in an expression?

Answer:

All ports are executed TOP TO BOTTOM in a serial physical ordering fashion, but they are done in the following groups:

 All input ports are pushed values first.

Then all variables are executed (top to bottom physical ordering in the expression).

Last - all output expressions are executed to push values to output ports

Friday, 25 September 2015

Aggregator Transformation Scenarios in Informatica


Aggregator Transformation In Informatica Scenarios
Aggregator Transformation In Informatica Scenarios



Suppose in our Source Table we have data as given below

 

Aggregator Transformation In Informatica Scenarios
Aggregator Transformation In Informatica Scenarios

We want to load our Target Table as
Aggregator Transformation In Informatica Scenarios
Aggregator Transformation In Informatica Scenarios



Describe your approach.

Answer:


Here our scenario is to convert many rows to one row, and the transformation which will help us to achieve this is Aggregator.

Our Mapping will look like this:


Aggregator Transformation In Informatica Scenarios
Aggregator Transformation In Informatica Scenarios




We will sort the source data based on STUDENT_NAME ascending followed by SUBJECT ascending.

Aggregator Transformation In Informatica Scenarios
Aggregator Transformation In Informatica Scenarios



Now based on STUDENT_NAME in GROUP BY clause the following output subject columns are populated as
 

 MATHS: MAX( MARKS, SUBJECT = ’Maths’ )
 

 LIFE_SC: MAX( MARKS, SUBJECT = ’Life Science’ )
 


PHY_SC: MAX( MARKS, SUBJECT = ’Physical Science’ )
Aggregator Transformation In Informatica Scenarios
Aggregator Transformation In Informatica Scenarios



Scenario Implementation 2

Source:

Aggregator Transformation In Informatica Scenarios
Aggregator Transformation In Informatica Scenarios




The expected output data: 100 XYZ AAA BBB CCC Which transformations are used for this?


Answer:

Use an Aggregator transformation with variable.

Blog Archive