Oracle Logbook

September 11, 2007

Understanding System Statistics

Filed under: Uncategorized — Helio Dias @ 8:50 pm

by Jonathan Lewis

Understanding the optimizer’s use of system statistics can make a big difference when migrating to a new version of the Oracle Database.

What is the most important component of the Oracle Database engine? My vote goes to the optimizer. Everything the database does is SQL, and every piece of SQL has to be translated into something that can work efficiently. Whatever you do with your data, the optimizer gets involved.

Transparent Data Encryption

Filed under: Uncategorized — Helio Dias @ 3:31 pm

By Arup NandaEncrypt sensitive data transparently without writing a single line of code.

It’s your organization’s worst nightmare: Someone has stolen backup tapes of your database. Sure, you built a secure system, encrypted the most sensitive assets, and built a firewall around the database servers. But the thief took the easy approach: He took the backup tapes, ostensibly to restore your database on a different server, start the database on it, and then browse the data at his leisure. Protecting the database data from such theft is not just good practice; it’s a requirement for compliance with most laws, regulations, and guidelines. How can you protect your database from this vulnerability?

One solution is to encrypt the sensitive data in the database and store the encryption keys in a separate location; without the keys, any stolen data is worthless. However, you must strike a balance between two contradictory concepts: the convenience by which applications can access encryption keys, and the security required to prevent the key theft. And to comply with company and federal regulations, you need a solution immediately, without any complex coding.

A new feature in Oracle Database 10g Release 2 lets you do just that: You can declare a column as encrypted without writing a single line of code. When users insert the data, the database transparently encrypts it and stores it in the column. Similarly, when users select the column, the database automatically decrypts it. Since all this is done transparently without any change to the application code, the feature has an appropriate name: Transparent Data Encryption (TDE).

Date Time operations

Filed under: Uncategorized — Helio Dias @ 11:52 am

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