SSAS: Process Incremental - What it is and isn't

SSAS provides Process Incremental as one of the processing options for cubes, measure groups and partitions. It is important to understand how Process Incremental works because it differs significantly from the seemingly equivalent Process Update for dimensions.

Process Incremental is extremely useful to process facts having journal entries. In a journal fact, updates to existing fact records are balanced by a corresponding negative or positive journal entry. In Process Incremental mode, a SQL query has to be provided that could identify the records inserted into the fact journal since last cube process.