Welcome to Group ORACLE SQL & PL/SQL GOLDEN DIARY

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I have three intentions behind writing the book. Intention 1: Interoperability among database versions Intention 2: Integration of related concepts for performance Intention 3: Creation of Golden Diary in a nutshell by practical examples These intentions have arisen based on the burning need of database users I have come across throughout my career with roles like PL/SQL developers , Database Administrators, Designers, Data analysts, Performance tuning analysts, Architects, Students, Professors, Interviewees and any DBMS enthusiast or aspirant for oracle certification. Some of these had extensive experience in what they do and have influenced me writing this book. This book will act as a reference guide for learning some very complicated concepts in a simple but precise way which are discussed through various case studies. This will give food for thought while devising mechanism for best possible approach for a database solution given the circumstances. The audience of this book would like to cover multiple versions of Oracle and the features it offers. Seeking the best approach for a challenge has not been easy in past as it required a large investment of time and effort to go through the vast amount of documentation. This 270 pages book facilitates that investment, by exploring and churning the vast archives of oracle documentation and producing the output in a nutshell which otherwise readers would need to spend time on. Will appreciate if you can give your feedback in amazon, createspace or any online portal or reach me author.asim@gmail.com This book is available in amazon and createspace https://www.createspace.com/6686735
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Subgroup Leader Leader Photo Location No Of Members No Of Views Last Post By LastPost Date Join
Table of contents for Oracle book IWC Admin UK 5 3338 Asim Chowdhury Nov 20, 2016 Join Subgroup
Flashback setup and data transfer to warehouse Asim Chowdhury UK 1 3252 Asim Chowdhury Nov 19, 2016 Join Subgroup


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Oracle book detailed Table Of Contents
Shared by Asim Chowdhury           Posted on Nov 20, 2016
Table of contents for Oracle book
Oracle sql & pl/sql golden diary
Oracle-sql-plsql-refactoring-TOC_pdf.pdf
 

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Oracle sql and pl/sql golden diary
Shared by Asim Chowdhury           Posted on Nov 17, 2016
Table of contents for Oracle book
about the book

This book is available in Amazon and

order the book in amazon or in createspace using below url

 

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Flashback introduction
Shared by Asim Chowdhury           Posted on Nov 17, 2016
Flashback setup and data transfer to warehouse
How to use Flashback

Chapter 4: Flashback setup and data transfer to warehouse (29 pages)

 Flashback transaction was introduced in Oracle 9i. When a query is long running, let us say for 1 hour, then it will display the data when the query was started 1 hour before. Even if some data undergone changes and committed by other transaction it will still display the data for point of time the query was started.

This is because Oracle maintains read consistent image in UNDO segment. So it is possible to get the old version of data till it is present in undo segment and not overwritten. This is how Oracle could show the image of the old version data even if new version of data is present by means of undo segment. So now if there is any mechanism for normal user to retrieve the old version of data from undo segment then we can fire a query and see the data.

However before Oracle 9i there was no such mechanism by which user could see the old version of data even if data was present in undo segment. The quest for helping user to see old version of data led to the introduction of the Flashback transaction in Oracle 9i

 

In this chapter we will explore all the dimensions of flashback, full examples of setup and data movement to warehouse using flashback mechanism, also we will explore related myth around this.

 

Tips 1: Why flashback was introduced?

Tips 2: What is the improvement of flashback in Oracle 11g and how to configure flashback?

Tips 3: What is the flashback mechanism?

Tips 4: How to check if flashback is configured in your system and in your tables?

Tips 5: Flashback query using method “timestamp” OR “scn”?

Tips 6: Move all versions of flashback data from transactional db to warehouse using STATIC method?

Tips 7: Move all versions of flashback data from transactional db to warehouse dynamically?

Tips 8: Restore table which is dropped using flashback?

Tips 9: Move specific date/time flashback data from transactional db to warehouse?

Tips 10: How many time a particular attribute in a row modified using flashback?

Tips 11: Improvement in auditing using flashback in 12c?

Tips 12: Improvement in tracking history for security related table using flashback in 12c?

Tips 13: import and export of flashback version history in 12c?

Tips 14: Free Flashback archive and OPTIMIZE option in 12c?

Tips 15: FLASHBACK magic exposed, Revealed for the first time

Here I covered some of the Tips related with flashback, for more details

order the book in amazon or in createspace using below url

https://www.createspace.com/6686735

Amazon india

Amazon UK

Amazon USA

 

 

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Flashback query using method “timestamp” OR “scn”?
Shared by Asim Chowdhury           Posted on Nov 17, 2016
Flashback setup and data transfer to warehouse
dealt with mechanism to see old versions of data using different methods

This tips dealt with mechanism to see old versions of data using different methods.

 To see the flashback data generated within certain timeframe you can use timestamp based approach or SCN based approach.

Timestamp based approach:

This approach takes hours when data is huge because it uses below explain plan

SCN based approach:

However USING the flashback version query based on SCN it is very quick. Here are the steps:

 1st get the corresponding scn for the timestamp as below: