Monday, March 9, 2015

The IsSorted property must be set to True on both sources of this transformation.

Step 1 
When using the Union All function it is important that the field on which you applied the union is sorted at the data sources using an 'order by'.

Step 2
Go to the Advanced Editor for the OLE DB Source to set IsSorted to True
Step 3
Set SortKeyPosition to 1 for the colum(s) you order on in step 1