Apparently its easy to confuse SSIS if you make too many copy and paste operations inside a Data Flow Task. In this case I added six data flows going through six Slowly Changing Dimension Transformations to one Data Flow Task. I know, I could have split the DFL into 6 seperate DFLs, but the data flows are very small. Each flow needs tracking information from a SSIS variable. That is done with a Derived Column Transformation. Each flow receives the same tracking variable so the Derived Column Transformation was configured once and then copied five times. The Data Flow Task runs fine but ends with an error even though all components inside the DFL are marked green! The DFL is marked red in the Control Flow editor.
The error thrown was:
The variable “System::LocaleID” is already on the read list.
- create a new package
- copy the misbehaving Data Flow Task and paste it in the new package
- delete the Data Flow Task
- copy and paste from the new package
Maybe it has something to do with IDs of components that are not getting updated correclty ?