DSXchange

There must be some transformation happening after the output from transformer,check for the NULL values and how you are handling in before and after datasets.

yes u need to hardcode or use data definiton if you had saved any.Just point to that schema in input and output.

When you have large amount of data comming from source its better to use normal lookup and if you are having incremental comming better go for sparse so that the performance will be good and when you use sparse look up use ORCHESTRATE.Key_field_name= Key_field_name. in where condition.