Monday, 20 June 2016

Getting started with Query Store feature in SQL Server 2016 – Part 2

Introduction


Query Store is a new feature in SQL Server 2016, which once enabled, automatically captures and retains a history of queries, execution plans, and runtime statistics, for your troubleshooting performance problems caused by query plan changes. This new feature greatly simplifies performance troubleshooting by helping you quickly find performance differences, even after a server restart or upgrade.

In the last article of the series, I discussed the advantages of this new feature, and explained some of the scenarios where you can use it. Finally, I talked about data capture processing, including what’s captured, and how it is retrieved when you enable the Query Store feature. In this article I am going to explain query execution flow when using Query Store and how it differs from regular query execution flow, its architecture and how to get started with it.

Monday, 6 June 2016

Altering an Existing Table to Support Temporal Data

What Is a Temporal Table?

A temporal table is just another SQL Server table that contains the old rows for a corresponding SQL Server table.  It is basically just a history table of old rows.  Every time an existing record is updated, the old row is placed in the associated temporal table automatically. A temporal table can also be called a history table.   Using this new feature in SQL Server 2016 means you can now track changes to a table overtime without having to write any application logic.  SQL Server will place the older rows in the temporal tables automatically.

Wednesday, 1 June 2016

Improved Defaults in Oracle Database 12c

The new DEFAULT clause provides better values for getting started and better performance.

Gordon has just completed some self-study Oracle Application Express training and is eager to start building applications to improve his skills and, more importantly, to rapidly deliver value to the business stakeholders in the company where he works.

He knows that Oracle Application Express is a database-centric development tool, so he wants to make sure he takes as much advantage as possible of the features available to him within the database so that the applications he builds will be more robust; will require less coding; and could even be ported to other front-end technologies, should the need arise. The applications will be simply a window into his data, but the data relationships, integrity, and controls will be within the database, alongside the data.