Bridging the gap between the logical and physical

There is a huge gap between the logical storage concepts in Oracle (tables, tablespaces) and the physical implementations (data blocks, cylinders, disks) and bridging this gap can be a real problem, especially for a beginner.

With all if it's sophistication, Oracle still does not know things outside the boundaries of the database:

- Oracle does not know the mapping of a logical tablespace to a physical disk

- Oracle has no idea what disks a data block resides upon

- Oracle does not know about competing demands from other instances on the server

In large systems itís possible to map specific tables to specific disk spindles so that you can see, at a glance, how your Oracle tables are being accessed.

For example it's critical to track large-table full-table scans against a table because that may indicate missing indexes:

http://www.dba-oracle.com/oracle10g_tuning/t_tracking_full_tables_scans.htm

You can track the usage of nested loops vs. hash joins for your tables:

http://www.dba-oracle.com/oracle10g_tuning/t_tracking_nested_loops_joins.htm

You can also use tools to show how your tables and indexes are being accessed.  I spent nearly a decade writing Ion for Oracle, a tool that shows you how your tables and indexes are being accessed by the SQL:

http://www.dba-oracle.com/ion_oracle.htm


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Can you see your database trends?

After several years of hard work, Ion for Oracle is finally available for general release.  Ion is unlike any other Oracle tool on the market, a tool that encapsulates expert techniques to allow a DBA to quickly visualize important trends and signatures.

Predictive analytics if the key to repairing Oracle problems before they cripple your database, and I created Ion for Oracle to allow any DBA to quickly identify changing workloads and unobtrusive patterns of data access.  To try Ion for free, see here:

www.ion-dba.com

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Need a health Check?

Oracle is the world's most complex and robust database and there are hundreds of sub-optimal setting that can cripple your database performance.

Burleson Consulting has a great Oracle health check where we identify all database bottlenecks to ensure that your mission-critical system is running at optimal speeds

Just call 800-766-1884 to schedule your health check.

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Need Oracle Training?

The very best Oracle training comes from Burleson Consulting, where you get an on-site visit by an experienced Oracle expert and author.  Whether it's one-on-one mentoring or getting a customized on-site Oracle training class, there is no substitute for BC Oracle training.  Just call 800-766-1884 for details, and check-out our on-site Oracle training catalog at the following link:

http://www.dba-oracle.com/bc-catalog.pdf

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How do I do that in Oracle?

Explore this series for a collection of tips that explain in detail how to perform specific tasks in Oracle related to database administration. Consisting of expert advice from top Oracle gurus, these how-tos provide step-by-step instructions to guide you through database administration processes related to installation and upgrades, backup and recovery and other Oracle basics.

http://searchoracle.techtarget.com/news/column/0,294698,sid41_gci1351260,00.html?mo=1&Offer=ORtextad0406tech