creating list from different columns from different tables

Hi,

The answer for your heading posted above is :

1. Create List,

2. Fetch Data column from table

3. Add it to the list.

Repeat 2>3 if holding list is different for all different table,

If it is same repeat 1>2>3.

and

The answer for your descripton posted above is :

once you have created the list with emailIds ex List1 and you already have List2 which already contains emailId.

The compariso is only left between 2 different list :

https://stackoverflow.com/questions/12795882/quickest-way-to-compare-two-generic-lists-for-differences#answer-12795900

Hope it helps.