The Data Integration Service creates an output file for each partition and then merges them into a single merge file. The Data Integration Service creates the individual target files using the output file name and output file directory values. The Data Integration Service sequentially adds the output data for each partition to the merge file, in the order that each writer thread completes. For example, if the writer thread for Partition2 finishes before the thread for Partition1, the Data Integration Service adds the data to the merge file in the following order: Partition2, Partition1.

The Data Integration Service creates a target file for each partition and creates a file list that contains the paths of the individual files. The Data Integration Service creates the individual target files using the output file name and output file directory values. If you write the target files to the merge directory or a directory under the merge directory, the file list contains relative paths. Otherwise, the file list contains absolute paths. Use this file as a source file if you use the target files as source files in another mapping.

The Data Integration Service concurrently writes the data for all target partitions to the merge file. It does not create intermediate files for each partition. Because the Data Integration Service writes to the merge file concurrently for all partitions, the order of the data in the merge file might not be sequential.