.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

Whatever folks say in previous answers are correct but I think that the most important aspect of using SSIS instead of coding is to have easy maintenance process and also a reusable product.

Answer 2

I guess it depends on what you are doing. SSIS is very powerful, just like old DTS. If you are loading lots of items and expect to have constant change, I would go SSIS all the way. If you are looking to load only a few items and it’s for lots of customers, I would put it in code. I prefer SSIS for in house ETL processes, but I use .Net at client shops when I need to load data from a legacy system into a SQL database. Now as I stated before if you have a lot of transformations and lots of different data silos to load, I think you would be crazy to do this in .Net and I would go SSIS. If you have only a few items to load and it’s for a single application and may be installed as part of an application at various clients, I would go .Net all the way. Just my 2 cents.

Answer 3

I think project time/budget constraints and the use of a standard tool are some of the biggest arguments for using SSIS. Creating an SSIS package is most of the times way faster than trying to code something similar in .NET.

But with that said, it seems like SSIS have a lot of pain points that sometimes might invalidate this argument. It did for me when developing a solution that needed to run in different environments at many different clients. SSIS simply looked too painful the more I evaluated it for the project. A properly architected .NET solution is easier to deploy, more reliable, more flexible, easier to understand and can also achieve very good performance.

IMHO: consider using SSIS for projects that you only need to deploy to one or maybe two in house SQL Server environments. Otherwise, the .NET approach will quickly become more appealing.

Answer 4

good question.

if the amount of data transfer huge? are you processing multiple data files and need transactions (both at file system level and database level)? are you dealing with multiple data sources at different locations (for eg ftp, local file system, database)?

if answers to above are yes then go ahead with ssis. basically .net is cool with small data import / export jobs, but when you have anything more complex, ssis is a definite winner

the other thing which i look at is - is it worth writing .net code when everything is available inside ssis. (dont mistake me - i love coding) however, anything you code, you need to maintain :-)

Answer 5

Bit late to answer this question but I hope it worth,

SSIS is often misunderstood when compared to programming language. SSIS is a framework whereas C# is a language on .NET Framework. I have extensive experience in handling & developing large data warehousing solution using (MSBI suite) and also had developed large websites (ASP.NET) - so I can't be biased.

SSIS if not used properly can decrease performance by par. SSIS packages have three kind of transformation:

1. Blocking transformation - which can only pass the data when above transformation is completed fetching all the rows and completed required calculation on it.
2. Semi-Blocking transformation - Which can pass partial data
3. Non-Blocking - which process the row as soon as it is ready

SSIS works exceptionally good with non blocking transformation with proper setting on control flow and data flow. I have used it on larger (over 2 TB of data warehouse) and I can guarantee that it was the fastest load experience. You can check Microsoft blog about We Loaded 1TB in 30 Minutes with SSIS, and So Can You

I agree that SSIS degraded performance when dealing with blocking transformation and they should be carried by T-SQL whenever required.

Coming to C#, I accept that SSIS uses .NET framework and data provider to accomplish task. But C#, as a language is bit more logical and must be treated to deal with business logic. For example, If we have to run exe with different parameter based on condition, you can write a package which will consider parameters and then logically decide what parameter needs to be passed to run an exe file. It would be lengthy process to do that in SSIS while I can do that easily in C# because logical thing can be easily done in language instead of a framework.

Now the point here is what is more convenient approach to solve your problem statement. SSIS is a sure winner loading large amount of records loading data from source to destination while C# is perfect for writing logic. Even if you like C#, I won't recommend you to choose for doing ETL (Extract Transform Load) operation on large data warehouse systems.

Answer 6

Day-to-Day Tasks , which are used by a SSIS Deveoper and are relatively easy as compared to .Net can include :

Data Comparison between the tables.

Conditional Splitting,data blocking the data on the basis of some logic.

Data Conversion,look up , merge , unionall , relatively easy to use.

File Handling(Modifying , validations).

Error Handing , Email Alerts.

Containers , FOR/FOReach loops are easy to use.

Posting data on web services is easy using the WebService task.

Checkpointing,Re-runablity of the data loads is easy to handle.

Debugging is easy in ssis - can be done on conatiner lever , package level.

Scripting can also be done , if the task is not available. Also , you can customize your own tasks