.Net vs SSIS: What should SSIS be used for?

Question

If I have the option of using .Net and can do data transformations just fine in .Net, when would I need SSIS? Is there a certain task

Answer 1

As the name suggests, SSIS is an integration system. It can be very difficult in .net to handle connectors to disparate data sources such as excel, teradata, oracle etc and also to live up to the responsibility to gracefully close those connections, garbage collection, handling memory issues.

So, SSIS is out of the box product perfect for scenarios where data not only needs to be pulled from, say, two different sources, but then a series lookups, transformations, merges, derivations and calculations need to be performed before writing it to a target location(be it sql server, a flat file or another db system).

SSIS also has checkpoints where, if the package fails due to any reason, it will pick up from where it left off (it needs to be configured as this is not default behavior).

In addition, SSIS will save you a lot of time because its tasks are reusable and its deployment process is fairly easy to implement and schedule, supported by great event handling.