Restrictions

System catalogs, MOTs, global temporary tables, local temporary tables, sequence tables, Ustore segment-page tables, unlogged tables, and compressed TOAST data are not supported.
This feature is valid only in ORA-compatible, PG-compatible, or B-compatible mode.
Ustore does not support encoding and decoding, thus offering a compression ratio lower than Astore.
When compression is enabled for ordinary tables, the space reserved for scale-out must be evaluated based on the size after decompression.
Compression scheduling is not supported during scale-out.
Before scale-out, check whether a compression task is being executed. If so, wait until the compression task is complete, or run DBE_ILM.STOP_ILM or DBE_ILM_ADMIN.DISABLE_ILM to stop the compression task. After the scale-out is complete, run DBE_ILM_ADMIN.ENABLE_ILM to enable it.
The partial decompression feature is added to the current version. As a result, some small tables are not compressed because their compression gain does not meet requirements. However, they can be compressed in earlier versions without the partial decompression feature. For example, a table containing only one column of the int1 type cannot be compressed since the current version.