Dinesh Asanka
Selecting the mining struture from the available list

Introduction to SQL Server Data Mining

July 23, 2019 by

Prediction, is it a new thing for you? You won’t believe you are predicting from the bed to the office and to back to the bed. Just imagine, you have a meeting at 9 AM at the office. If you are using public transport, you need to predict at what time you have to leave so that you can reach the office for the meeting on time. Time may vary by considering the time and the day of the week, and the traffic condition etc. Before you leave your home, you might predict whether it will rain today and you might want to take an umbrella or necessary clothes with you. If you are using your vehicle then the prediction time would be different. If so, you don’t need to worry about the rain but you need to consider the fuel level you need to have to reach to the office. By looking at this simple example, you will understand how critical it is to predict and you understand that all these predictions are done with your experience but not by any scientific method.

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Daniel Calbimonte
SQL Server on-premises or SQL Cloud

SQL Server download guide

July 22, 2019 by

Introduction

This article serves as a SQL Server Download guide for both beginners and beyond. Some years ago, it was pretty simple to download the installer because you had all the components installed. Now, it is harder because you need to install several components, there are several versions and editions. This guide will help you to understand which version and edition needs to be downloaded.

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Ranga Babu
adding database to an existing failover group

Azure SQL Server auto-failover groups

July 18, 2019 by

In this article, we will review how to set up auto-failover groups in Azure SQL Server and how failover group is different from active geo-replication in Azure. Auto-failover group is an Azure SQL database feature that replicates one or a group of databases to the secondary Azure SQL server in the cross-region. We cannot have a secondary server in the same region. This feature is used to failover all the databases in the failover group in case of disaster and the failover is automatic.

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Ranga Babu
Geo-Replication

Azure SQL database Geo-Replication

July 15, 2019 by

In this article, we will review how to set up Geo-Replication on Azure SQL databases. Geo-Replication is an Azure SQL database feature that allows you to create a readable secondary database in the same region or cross-region. We can failover to the secondary database in case of an outage for a long time on the primary database server. We can also use this feature to migrate a database from one server to another server in the same or cross region with minimal downtime. Geo-replication uses the Always-on feature to replicate committed transactions to the secondary database asynchronously.

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Rajendra Gupta
Availability group validations

Applying Transaction Logs to the Secondary Replica in SQL Server Always On Availability Groups

July 12, 2019 by

Introduction

SQL Server Always On Availability Groups provides HADR solutions for the SQL databases. Here HA refers to high availability and DR refers to disaster recovery. The priority of this feature is to keep the database highly available and then provide Disaster recovery. Due to this reason, if the secondary replica goes down in a synchronous data commit mode, SQL Server changes commit mode to Asynchronous so that users can continue run the transactions and a secondary replica can be in sync later once it bought up. SQL Listener also points to the primary replica and continues redirects connection to the primary replica.

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Rajendra Gupta
difference between RANK() and DENSE_RANK() functions

Overview of SQL RANK functions

July 3, 2019 by

We perform calculations on data using various aggregated functions such as Max, Min, and AVG. We get a single output row using these functions. SQL Sever provides SQL RANK functions to specify rank for individual fields as per the categorizations. It returns an aggregated value for each participating row. SQL RANK functions also knows as Window Functions.

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Bojan Petrovic

Optimizing SQL Server index strategies

July 2, 2019 by

Index strategies overview

This article is about techniques for optimizing the SQL Server indexes strategy. It is an appendix of the SQL index overview and strategy article in which I covered different areas like what indexes actually do, how to create them, and I briefly mentioned some index design guidelines. Furthermore, I also presented an example of how to design them by tuning and optimizing queries, so I’ve really tried to cover all but there is always more when it comes to SQL Server indexes.

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