Multi-Value Compression Guideline
Compress column values only when compression does not have the net effect of reducing storage capacity. For information about how to make this determination, see “Calculating the Efficiency of Multi-Value Compression” on page 725.
Multi-value compression produces shorter rows, which in turn generally produce more high‑performing applications.
Note that column multi-value compression, once defined for base table columns, is inherited by join indexes defined on those value‑compressed columns as well retained as a property of spool files containing data from the table as well, so compression is not just a property of data stored on disk.