Wednesday, August 02, 2006

Failure - Data Source Does Not Exist..!

One of the SSIS interfaces I have been working on a project pulls data from 10 identically structured databases. The task we had was to pull data for a particular day, supplied via a parent variable, and place the data into a single file for import into the staging database of the BI infrastructure.

The problem was that if one of the data sources was down, the WAN connection playing up or there was any other problem that would cause one of the data sources to fail, the entire package would fail. We didn’t want this behaviour because the client wanted as much data as possible rather than a complete failure.

For starters the OLEDB source wasn’t going to help us in this situation so we had to go for a scripted data source and changing the Acquire Connection code with a simple Try-Catch statement. This worked well and does the trick. We can run the entire package without any problems building up the connection string as variables that are passed into the script and connecting to the required single data-source. But then another requirement popped up.

How do I know when a data-source has failed, I don’t want the package to fail but a warning would be nice and enable us to capture the event in our logging mechanism. Enter the FireWarning method. This little diamond, along with its cousins FireError, FireInformation and FireProgress allows you to place custom entries into the SSIS logging.

I have an example package built on Adventure Works if anyone wants it and, although quite simple, I have come across a number of instances where connecting to multiple data sources (including flat file connections) where this behaviour is needed.

1 comment:

Anonymous said...


this is just what i am looking for. could you post ur example.