You can use parameter when you want to drive the ETL outside of the informatica code. Say for example, you want to extract different set of data based on the value you decide, it's not a good method to change the code every time. So you create a parameter and use that as a filter condition in the source.
similarly, you can create session parameters to read from different sources based on a parameter value specified for the connection. You can parameterize connections, file names, directories etc. There are bunch of parameters you can override. You can also parameterize some of the workflow level parameters. it's nice to go through the infa documentation and find out what are parameters you can use and give a try.
Defines a value that can change from session to session, such as a database connection or file name.
Informatica WorkFlow manager also allows you to create userdefined session parameters such as
Database connections, Source File names, Target File Names etc...
Say, Parameterize the 'Source File name' or 'Source File Directory' to the required name and location.
yeah, as abdul said, it's nice to go thru documentation and try
mostly session parameters are used
source database ex user name :scott
after some days ur database changes like user name:system
this situtions we need use session parameters.
below files also we can use session parameters.
soruce file names, target file names ,sesssion log file names,rejected file names and bad file names
Provide Flexibility to run sessions for different files and databases:
With the help of sessions parameter (File and database connection parameter) we can read from different files and write to different database tables just with one session. What you have to do is that you have to provide different parameter files to pmcmd command,
First time session run – ParamFile1 which will read from File1 and will write DatabaseTable1.
Second Time session run – ParamFile2 which will read from File2 and will write to DatabaseTable2.
Go to => Sessions – Properties tab – parameter file attribute
Using session parameter you can drive the ETL outside of the informatica code.Thats nothing else you can provide dynamisam to your session for choosing Database connections dynamically.