Maintain the row order of the input data to the transformation. Select this option if the Integration Service should not perform any optimization that can change the row order.

When the Integration Service performs optimizations, it might lose an order established earlier in the mapping. You can establish order in a mapping with a sorted flat file source, a sorted relational source, or a Sorter transformation. When you configure a transformation to maintain row order, the Integration Service considers this configuration when it performs optimizations for the mapping. The Integration Service performs optimizations for the transformation if it can maintain the order. The Integration Service does not perform optimizations for the transformation if the optimization would change the row order.