SQL> connect sh/oracle@orcl Connected. Creating a HCC Table Compressed for Query High ============================================== SQL> create table sales_queryhigh ( empname varchar2(30), empno number, empdescr varchar2(100), hire_date date ) tablespace users compress for query high; Table created. SQL> select table_name,compression,compress_for from user_tables where table_name='SALES_QUERYHIGH'; TABLE_NAME COMPRESS COMPRESS_FOR ------------------------------ -------- ------------ SALES_QUERYHIGH ENABLED QUERY HIGH Creating a HCC Table with HCC Partitions ======================================== SQL> create table orders ( 2 cid number, 3 pid number, 4 sid number, 5 price number(5,2), 6 discount number(3,2), 7 odate date) 8 partition by range (cid) 9 (partition p1 values less than (100000) nocompress, 10 partition p2 values less than (200000) compress for archive low, 11 partition p3 values less than (300000) compress for query high, 12 partition p4 values less than (maxvalue) compress for query low) 13 enable row movement 14 ; Table created. SQL> select table_name,compression,compress_for from user_tab_partitions where table_name='ORDERS'; TABLE_NAME COMPRESS COMPRESS_FOR ------------------------------ -------- ------------ ORDERS DISABLED ORDERS ENABLED ARCHIVE LOW ORDERS ENABLED QUERY HIGH ORDERS ENABLED QUERY LOW Compression attributes for Tablespace ===================================== SQL> connect sys/oracle@orcl as sysdba Connected. SQL> create bigfile tablespace bigtbs datafile '+DATA' size 1G autoextend on next 1m extent management local autoallocate segment space management auto default compress for query low; Tablespace created. SQL> select tablespace_name, def_tab_compression, nvl(compress_for,'NONE') compress_for from dba_tablespaces; where tablespace_name='BIGTBS'; TABLESPACE_NAME DEF_TAB_ COMPRESS_FOR ------------------------------ -------- ------------ SYSTEM DISABLED NONE SYSAUX DISABLED NONE UNDOTBS1 DISABLED NONE TEMP DISABLED NONE USERS DISABLED NONE EXAMPLE DISABLED NONE BIGTBS ENABLED QUERY LOW 7 rows selected. SQL>
Wednesday, May 25, 2016
Oracle Exadata Hybrid Columnar Compression (EHCC) Levels
Subscribe to:
Post Comments (Atom)
No comments:
Post a Comment