Guenadi N Jilevski's Oracle BLOG

Oracle RAC, DG, EBS, DR and HA DBA BLOG

New Index enhancement in Oracle 12c Part 1 – Multiple indexes on the same set of columns

New Index enhancement in Oracle 12c Part 1 – Multiple indexes on the same set of columns

 

In the article you will have a look at the following new index feature in oracle 12c ‘Multiple indexes on the same set of columns’. Staring with Oracle 12c you are enabled to create multiple indexes on the same set of columns. The following different indexes can be created on the same set of columns.

  1. Index of different type. Bitmap index and B-tree index.
  2. Partitioned index and not partitioned index.
  3. Locally partitioned index and globally partitioned index.
  4. Indexes differing in partitioning range and hash.
  5. Indexes that have different uniqueness properties. You can have both unique and non-unique index on the same set of columns.

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November 1, 2016 Posted by | oracle | Leave a comment

In database row archiving in Oracle 12c

 

In the article you will have a look at the new Oracle 12c feature called in database row archiving available since Oracle 12c. In Oracle versions prior to 12c all table data was an active visible set of data, that is subject to DML performed by the application. In Oracle 12c the In database row archiving feature enable us to have two sets of table data an active visible set of data that coexists with archived and invisible set of data. The in database row archiving is a table feature that get enabled at table level with the ROW ARCHIVAL clause of create table or alter table. Once the feature enabled a new hidden table column ORA_ARCHIVE_STATE appears. This column can be used in SELECT list and can be updated but is not visible in describe issued from sqlplus prompt. It is the ORA_ARCHIVE_STATE column value that determines whether the row belongs to the active set of data or the archive invisible set of database. When rows get inserted into a table the ORA_ARCHIVE_STATE is 0. By modifying the ORA_ARCHIVE_STATE to 1 the row is transferred into the invisible archived set of table data. CTAS does create a new table but does not propagated the In database row archiving feature from the source table. The application can control the visibility to the active and invisible archived set of data using the ALTER SESSION SET ROW ARCHIVAL VISIBILITY [ALL/ACTIVE] statement at session level.

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October 14, 2016 Posted by | oracle | Leave a comment

Using PL/SQL to run the SQL tuning Advisor in 11gR2

Using PL/SQL to run the SQL tuning Advisor in 11gR2

In the article we will have a look at the steps to invoke and run the SQL Tuning Advisor using the interface of the PL/SQL packages provided by Oracle. The SQL Tuning Advisor can be run in an alternative way using the OEM 12c Cloud Control interface. We will not cover the OEM 12c CC interface.

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May 7, 2016 Posted by | oracle | Leave a comment

Star Transformation in 11gR2

Star Transformation in 11gR2

 In the article we will review the prerequisites for the CBO to perform a star query transformation. We will use the SH samples schema. We will look at two cases with and without a bit map join index. Continue reading

May 4, 2016 Posted by | oracle | Leave a comment

Using the SQL ACCESS Advisor PL/SQL interface

Using the SQL ACCESS Advisor PL/SQL interface

In the article you will have a look at an example of using the SQL Access Advisor PL/SQL interface to obtain the access path and object structures change recommendations.

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March 2, 2016 Posted by | oracle | Leave a comment

Configuring Fast Start Failover

Configuring Fast Start Failover

In the article you will have a look at an example of configuring Fast Start Failover (FSFO). Oracle 11gR2 has been used. The configuration is based on server zeus running the PRA database and server Apollo running the STBY2 database. The STBY2 is the standby database.

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March 2, 2016 Posted by | oracle | Leave a comment

Session failover using Data Guard 11gR2

Session failover using Data Guard 11gR2

In the article we will see the session failover using an Oracle 11gR2 Data Guard. The feature is available since Oracle 11gr2 when the services become a CRS resource. The software used is Oracle RDBMS 11gR2. There are two nodes zeus running the PRA primary database and a STBY1 standby database and apollo running the STBY” standby instance. We will demonstrate a connection failover of a connection to a service on the primary while transitioning the STBY2 standby database open as an ADG as a new primary.

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March 2, 2016 Posted by | oracle | Leave a comment

Packt’s $5 eBonanza returns

Packt’s $5 eBonanza returns

Following the success of last year’s festive offer, Packt Publishing will be celebrating the holiday season with an even bigger $5 offer.

From Thursday 18th December, every eBook and video will be available on the publisher’s website for just $5. Customers are invited to purchase as many as they like before the offer ends on Tuesday January 6th, making it the perfect opportunity to try something new or to take your skills to the next level as 2015 begins.

With all $5 products available in a range of formats and DRM-free, customers will find great value content delivered exactly how they want it across Packt’s website this Xmas and New Year.

Find out more at www.packtpub.com/packt5dollar

December 31, 2014 Posted by | oracle | Leave a comment

2014 in review

The WordPress.com stats helper monkeys prepared a 2014 annual report for this blog.

Here’s an excerpt:

The Louvre Museum has 8.5 million visitors per year. This blog was viewed about 120,000 times in 2014. If it were an exhibit at the Louvre Museum, it would take about 5 days for that many people to see it.

Click here to see the complete report.

December 29, 2014 Posted by | oracle | Leave a comment

The best deals from Packt Publishing

This month marks 10 years since Packt Publishing embarked on its mission to deliver effective learning and information services to IT professionals.

To celebrate this huge milestone, Packt is offering all of its eBooks and Videos at just $10 each for 10 days – this promotion covers every title and customers can stock up on as many copies as they like until July 5th. Please visit Packt Publishing here.

July 1, 2014 Posted by | oracle | 2 Comments