The Data Integration Service can create partitions for a mapping that establishes a sort order. You can establish sort order in a mapping with a sorted flat file source, a sorted relational source, or a Sorter transformation. When the Data Integration Service adds a partition point to a mapping, it might redistribute data and lose the order established earlier in the mapping. To maintain order in a partitioned mapping, you must specify that Expression, Java, Sequence Generator, SQL, and Write transformations maintain the row order in the transformation advanced properties.