Susantha Bathige

Understanding Skewed Data in SQL Server

May 22, 2017 by

Introduction

I recently did some research to analyze skewed data distribution in SQL Server. This article is the outcome of my analysis to share with SQL Server community.

SQL Server understands its data distribution using statistics. The SQL Server query optimizer then uses the statistics to calculate estimated row counts when executing the queries submitted by users. The accuracy of estimated row count is crucial to get optimal execution plans. The SQL Server query optimizer is a complex mathematical component and it does a decent job to create better execution plans during a very short period of time.

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David Alcock

Monitoring SQL Server with Dynamic Management Objects – Requests

May 17, 2017 by

In my last post, Monitoring SQL Server with dynamic management objects – Sessions and connections, I introduced the concept of using T-SQL queries to monitor SQL Server using Dynamic Management Views. The article demonstrated how we can use two views, namely sys.dm_exec_sessions and sys.dm_exec_connections to view activity on our instance of SQL Server and we achieved this by utilising some of the functionality available to us within T-SQL like joins, aliases and functions, all of which helped us develop a query to return monitoring information to us.

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Gerald Britton

Discovering database specific information using built-in functions and dynamic management views (DMVs)

May 15, 2017 by

Introduction

In the last two articles on dynamic management views in SQL Server, Discovering SQL server instance information using system views and Discovering more SQL Server information using the built-in dynamic management views (DMVs), we used DMVs to discover a fair bit of information about the SQL Server instance we’re connected to. In this article, we’ll begin diving in to database specifics. There is a lot of territory to cover! We’ll also use several of the built-in functions that come with SQL Server.

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David Alcock

Monitoring SQL Server with Dynamic Management Objects – Sessions and connections

May 12, 2017 by

A fundamental task of Database Administrators is monitoring SQL Server performance. Whilst SQL Server does give us a user interface inside management studio that enables us to view current activity (in the rather aptly named Activity Monitor) this article is going to focus on querying Dynamic Management Objects with T-SQL to return various pieces of useful process information that we can use to monitor server usage.

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Prashanth Jayaram

Installation of SQL Server vNext CTP on Linux Distribution CentOS 7

May 10, 2017 by

It was a paradigm shift in December 2016, when Microsoft made their SQL Server database available for Linux; it was the first time in history that Microsoft ever designed SQL Server to run on a non-Windows operating system. SQL Server vNext was released for public preview so the user community could test and deploy SQL Server on a Linux operating system. Microsoft took a major step in diversifying the database technology into the non-windows platform for the first time.

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Sifiso Ndlovu

How to Avoid Package Design Flaws When Sourcing Data From Flat Files

May 10, 2017 by

As developers of SQL Server Integrations Services (SSIS) solutions, we have more than likely configured Flat File Connections as sources in our Data Flow Tasks. Whilst any unforeseen changes to the structure and formatting of flat files will invariably cause SSIS packages to fail, as developers we can still do a lot in reducing unnecessary SSIS package failures relating to data coming out of flat files. In this article, we offer recommended development practices to some flat file source errors that occur as a result of poor SSIS development practices.

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Marko Zivkovic
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How to connect and use Microsoft SQL Server Express LocalDB

May 9, 2017 by

Microsoft SQL Server Express LocalDB is intended for developers, it is very easy to install and doesn’t require any complex configuration task to create an instance or to use the database. The Introduction on the installation of Local DB be found on “How to install Microsoft SQL Server Express LocalDB” article.

This article will show different ways of connecting to LocalDB and how to create and use an instance of LocalDB.

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Marko Zivkovic
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How to install Microsoft SQL Server Express LocalDB

May 9, 2017 by

Microsoft SQL Server Express LocalDB, a solution primarily intended for developers, is a lightweight version of SQL Server Express. It is very easy to install and set up. The installation copies a minimum set of files which are necessary to start SQL Server Database Engine. LocalDB supports the same T-SQL language and has the same limitations as SQL Server Express.

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Daniel Tikvicki

How to set and use encrypted SQL Server connections

May 8, 2017 by

As the standard for securing the host-server interaction, Secure Sockets Layer or SSL is implemented in a Web environment. However, the SSL can provide the encrypted connection and data transfer between a particular SQL Server instance and a client application. A trusted SSL certificate validates the SQL Server instance when the client application requests encrypted connection (or vice versa), while the SQL Server must be configured to follow the certificate authority (CA). This means that a certificate must be “signed” by a trusted source.

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Neeraj Prasad Sharma

Introduction to Nested Loop Joins in SQL Server

May 8, 2017 by

A relational database system uses SQL as the language for querying and maintaining databases. To see the data of two or more tables together, we need to join the tables; the joining can be further categorized into INNER JOIN, LEFT OUTER JOIN, RIGHT OUTER JOIN, FULL OUTER JOIN, and CROSS JOIN. All these types of joins that we use are actually based on the requirement of the users.

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Sifiso Ndlovu

How to use Columnstore Indexes to improve your Data Warehouse Staging Environment

May 4, 2017 by

My team and I were recently tasked with refactoring older data marts, particularly those that were created with SQL Server 2008 in mind. As we all know, SQL Server has undergone significant changes since the release of SQL Server 2008. One of those changes relates to the introduction of columnstore as an alternative to the traditional B-tree index (rowstore). Whilst most of the existing documentation relating to columnstore seem to focus on the benefit of columnstore against data warehouse workloads, in this article I argue that the usage of columnstore index should not be limited to facts and dimensions instead let’s introduce it in our data warehouse staging environments too.

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