11G new Features-OLTP Table Compression

In previous versions, data could only be compressed during bulk load operations, such as direct load, create table as select operations. Data cannot be compressed during DML operations.

In 11g, Oracle extends table compression to OLTP workloads, such as the ability to compress data at insert time.

OLTP compression can save 50-70% of space. OLTP compression not only reduces write performance, but also increases read performance (reading compressed data directly).

Set Table compression

Normal compression table:

1. Create a compressed table using traditional methods

Sql> CREATE TABLE Ct1 (ID number) compress;

2.11G new syntax method to create a compressed table

 for direct_load operations;

3. Create an OLTP compression table (to compress data when DML operations)

 for all operations;

Monitoring table Compression

Select  from User_tables; table_name                     COMPRESS compress_for--------------------------------------------------DEPT                           DISABLEDCT3                            enabled  OLTPCT2                            enabled  BASICCT1                            enabled  BASIC

11G new Features-OLTP Table Compression