It looks like temporary table can not be compressed by using Oracle Advanced Compression Feature in 12.1.0.2.
SQL> alter session set current_schema=testuser; SQL> CREATE GLOBAL TEMPORARY TABLE TEST_TBL ( id number, name varchar(20), CONSTRAINT TEST_TBL_PK PRIMARY KEY (id) ENABLE ) ON COMMIT DELETE ROWS; Table created. SQL> insert into TEST_TBL values ( 1,'testuser'); 1 row created. SQL> select * from TEST_TBL; ID NAME ---------- -------------------- 1 testuser SQL> alter table TEST_TBL move compress for all operations; alter table TEST_TBL move compress for all operations * ERROR at line 1: ORA-14451: unsupported feature with temporary table SQL> commit; Commit complete. SQL> select * from TEST_TBL; no rows selected