Oracle® Database. SQL Reference. 10g Release 2 (10.2). B14200-01. June 2005
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You can specify table compression for the following portions of a heap-organized table:
- For an entire table, in the physical_properties clause of relational_
table or object_table
- For a range partition, in the table_partition_description of the range_
partitioning clause
- For a list partition, in the table_partition_description of the list_
partitioning clause
- For the storage table of a nested table, in the nested_table_col_properties
clause
То есть для вас подходит п.1.
Попробуйте
ALTER TABLE my_part_table MOVE COMPRESS;