How to use mapping parameters and what is their use
In designer u will find the mapping parameters and variables options.u can assign a value to them in designer. comming to there uses suppose u r doing incremental extractions daily. suppose ur source system contains the day column. so every day u have to go to that mapping and change the day so that the particular data will be extracted . if we do that it will be like a layman's work. there comes the concept of mapping parameters and variables. once if u assign a value to a mapping variable then it will change between sessions.