Oracle Database 11g

DB_ULTRA_SAFE parameter

DB_ULTRA_SAFE is a new parameter introduced in 11g. It provides an integrated mechanism to offer protection from various possible data corruptions. and provides critical high availability benefits for Oracle Database. Setting DB_ULTRA_SAFE initialization parameter will configure the appropriate data protection block checking level in the database. It will control DB_BLOCK_CHECKING, DB_BLOCK_CHECKSUM, and DB_LOST_WRITE_PROTECT. DB_BLOCK_CHECKING controls whether or not Oracle performs block checking for database blocks. DB_BLOCK_CHECKSUM determines whether DBWn and the direct loader will calculate a checksum and store it in the cache header of every data block when writing it to disk. DB_LOST_WRITE_PROTECT enables or disables lost write detection. Read More

Compress table

Scenery: Mass distribution of rich and multimedia content over the Internet, made possible through advancements in broadband technologies, also contributes to the growth in overall data volume. The enormous growth in the volume of data that needs to be retained online makes storage one of the biggest cost elements of most IT budgets. The compression clause can be specified at the tablespace, table or partition level with the following options: NOCOMPRESS – The table or partition is not compressed. This is the default action COMPRESS – This option is considered suitable for data warehouse systems OMPRESS FOR ALL OPERATIONS – This option is Read More

A new feature in Oracle 11g: ACTIVE DUPLICATE

Very often we need to make copies of the production database in test environments to be able to perform functional tests which can then be issued on production. To make a copy of the database there are several methods. Some of these are: •    Export / import mode (which uses the utility expdp / impdp made available to Oracle and that will be the subject of future articles); •    Cold Copy  (made with a physical copy of the file; if the source is down you do not need a step of recovery, while if the source is active then you Read More