New features in Oracle RDBMS 10.2.0.4

I found this from a presentation on new features in Oracle RDBMS 10.2.0.4 for SAP

RAC Features

Non-blocking Thread Architecture for CRS Background Processes

• Improved Cluster Stacks:

• AIX 5.3 / 6.1 – GPFS 3.2

• Faster Detection of Node Failures

• Improved Recovery Times after Node Failures

• Linux – OCFS 1.4

• Included in SLES10 SP2 and RHEL5.2

• New Features include Online Resizing, Sparse Files, Shared writable mmap, Preparation for Cluster LVM (Stretched Cluster)

Cost Based Optimizer

• Multi Column Statistics (MCS)

• Dynamic Sampling

Benefit of MCS

• Allows detection of column correlation for concatenated indexes

• Important especially for bind variable usage

Example: create index aaa_1 on aaa (www, xxx, yyy);

create index aaa_2 on aaa (www, xxx, zzz);

select * from aaa where www = :a0 and xxx = :a1 and yyy = :a2;

• Without MCS wrong index aaa_2 may be chosen !

• MCS enabled in 10.2.0.4 through following parameters

• _fix_control=5765456:7

• _fix_control=6221403:ON

Benefit of Dynamic Sampling

• Allows better calculation of optimizer statistics due to non-existing or outdated statistics for tables

• Statistics are collected during query execution by sampling data

• Dynamic Sampling enabled in 10.2.0.4 through following parameter

• Optimizer_dynamic_sampling = 6

Opatch 10.2.0.4 and OCM

• Patchset 10.2.0.4 includes OPatch 10.2.0.4

• version 10.2.0.4.2 or 10.2.0.4.3 (depending on platform)

• includes OCM (Oracle Configuration Manager)