I have an SSIS script component that picks the first row from each group and passes that to the output. This component was developed first in 2005 and then migrated to 2008. That worked fine. The code is basically:
If (Row.Keys <> PreviousKeys)
PreviousKeys = Row.Keys
Now that I am migrating to 2012 I having issues. Downstream from the script component it is the right-side input to a MERGE JOIN. I'm getting this error from the MERGE JOIN:
> Input columns must have output columns. There are input columns with a
> usage type of read-only that do not have associated output columns.
The only thing I found that sets columns to read-only is in the input column selection of my script task. When I change the script so that it just sets a boolean field on the row to TRUE when the keys change the message goes away. I'm taking this as a confirmation that the script component was the source of read-only problem. Now I have a new problem though. With this change to the script the MERGE JOIN now thinks that the data are unsorted.