Eating An Elephant – How To Work With Huge Datasets In Oracle And SQL Server

Simplifying complex problems is difficult but when done, the rewards are definitely worth it. How I single-handedly managed to migrate 55 Billion rows in 4000+ tables: Last year, I created PowerPump a PowerShell based data copy server which continuously migrated 4000+ Oracle tables to SQL Server. It was no simple task given that I had … Continue reading Eating An Elephant – How To Work With Huge Datasets In Oracle And SQL Server

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Oracle – Back To The Past – Using The Oracle Flashback Query Feature

Go back in time and look how something looked then - Isn’t this one of those things that is really cool? In Oracle, the set of features that enable this capability are clumped under “Oracle Flashback Features”. Technically, they can be bucketed as: Flashback query – as the name means, retrieve data as of a point … Continue reading Oracle – Back To The Past – Using The Oracle Flashback Query Feature

Oracle – TRUNCATE vs DELETE – Spoiler: TRUNCATE Wins & Why? Hours vs Seconds!

Why DELETE is bad? In Oracle, when it comes to deleting  ** A L L **   the data from a table (clearing the contents of a staging table for example), using a DELETE statement is the most inefficient choice. Here are some reasons why DELETE is bad It uses UNDO It uses REDO It fires … Continue reading Oracle – TRUNCATE vs DELETE – Spoiler: TRUNCATE Wins & Why? Hours vs Seconds!

Oracle UNDO – A Basic Explanation

You might have heard the terms UNDO and REDO thrown around in conversations around space usage. In this tip, let us get a basic idea of what UNDO (formerly called ROLLBACK) is in Oracle. I promise you that this will be an interesting read and you will be happy you read this. Unlike SQL Server … Continue reading Oracle UNDO – A Basic Explanation