Features

Jefferson Elias

How to take advantage of the SQL Server’s transaction log?

April 11, 2016 by

Introduction

SQL Server keeps track of all database modifications and every database transaction. This is done in a file called the transaction log or TLOG. This transaction log is particular to a SQL Server database and there is, at least, one transaction log per SQL Server database.

As explained on MSDN, the transaction log is a critical component of the database and, if there is a system failure, the transaction log might be required to bring your database back to a consistent state. The transaction log should never be deleted or moved unless you fully understand the ramifications of doing this.

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Ahmad Yaseen

How to configure SQL Server mirroring on a TDE encrypted database

February 19, 2016 by

Securing and encrypting sensitive data stored in your production databases is a big concern, especially the databases storing the organization’s financial data and customers’ confidential information.

SQL Server offers multiple encryption methods in the cell, table and database levels. And in this article, we are interested in a SQL Server database encryption method, introduced in SQL Server 2008, called Transparent Data Encryption (TDE). SQL Server TDE provides encryption on the database file level; it encrypts the database (.MDF), (.LDF), (.NDF), (.BAK), (.DIF), (.TRN) and snapshot files.

The main purpose of this article is showing how we could setup a mirroring site for a database encrypted using SQL Server Transparent Data Encryption. But before starting the demonstration, it is better to introduce TDE first.

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Timothy Smith

Understanding the distribution scale of transactional and snapshot replication

January 25, 2016 by

Background

If an environment chooses to use snapshot or transactional replication, one useful exercise is to ask the technical end user (or client) what they think replication does. If you have access to a white board, you can even ask them to demonstrate what they think replication will do for their data. Generally, these technical end users will plot something similar to the below image, where we see a table with data being copied to another table with data.

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Miroslav Dimitrov

SQL Server Transactional Replication Moving Distribution Database – step-by-step guide

November 27, 2015 by

SQL Server replication is a relatively old high-availability solution part of the Microsoft world. In fact, there have not been any significant changes to this solution in the recent versions SQL versions, but it is still a widespread mechanism for distributing objects from one database to another and synchronize them. Replication is very useful when you have remote and mobile users accessing your data. Let’s cut to the chase and give you more details about our specific case. 🙂

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Ed Pollack

The SQL Server Query Store in Action

November 26, 2015 by

Introduction

The Query Store is a new feature in SQL Server 2016 that will greatly improve the process of performance tuning! The biggest limit of the query plan cache and the dynamic management views that relates to it is that it is very temporary. Queries are only accessible for as long as they are in cache, and as a result there is no way to travel back in time to determine what happened at 9am yesterday, or why performance worsened over a week-long period.

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Brian Bønk Rueløkke

Query Store – the next generation tool for every DBA

November 13, 2015 by

Along with the release of SQL server 2016 CTP 3 now comes the preview of a brand new feature for on premise databases – the Query Store. This feature enables performance monitoring and troubleshooting through the log of executed queries.

This blogpost will cover the following aspects of the Query Store feature:

  • Introduction
  • How to activate it
  • Configuration options
  • What information is found in the Query Store
  • How to use the feature
  • What’s in it for me
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Miroslav Dimitrov

SQL Server Transaction Log – Part 3 – Configuration Best Practices

May 4, 2015 by

It has been a while since the last transaction log article has been published, so I hope you do remember where this series is heading to. In the former posts, we have examined the Log Structure and Write-Ahead Algorithm (part 1) and the Top Reasons for Log Performance Problems (part 2). Taking into consideration this knowledge, we will review some best-practices for transaction log configuration in order to decrease the chance of experiencing log bottlenecks.

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Daniel Calbimonte

How to create a Database Mirroring

March 6, 2015 by

Sometimes our Database fails and we need to reestablish the Database services immediately. Is there a SQL Server solution for high availability?

With Database Mirroring, we can have a replica of the database ready to be used if the main database fails. In this article, we will give a step-by-step tutorial about Database Mirroring. There are other solutions for high availability like high AlwaysOn, Clusters and Log Shipping, but in this chapter, we will start with Mirroring.

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Minette Steynberg

Reading the SQL Server Transaction Log

February 9, 2015 by

Introduction

There has always been some debate as to whether or not there are real benefits to be gained from accessing the information in the transaction log. This article will endeavor to answer that question by looking at the following:

  • What is the SQL Server Transaction Log?
  • What information is stored in the transaction log?
  • What can be gained by accessing the information in the transaction log?
  • How does the transaction log work?
  • What tools are available for reading the transaction log?
  • And ultimately, is this something we should be doing at all?
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Miroslav Dimitrov

SQL Server Transaction Log – Part 1 – Log Structure and Write-Ahead Logging (WAL) Algorithm

December 18, 2014 by

SQL Server transaction log is one of the most critical and in the same time one of the most misinterpreted part. While being neglected, it can easily become a bottleneck to our SQL Server environment. We need to have this in mind and to take care of our transaction logs in order to streamline the performance of our queries and increase log’s throughput.

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Derik Hammer

Disaster Recovery Planning with Always-On Availability Groups

December 17, 2014 by

When I configured my first Always-On Availability Group, I setup a Windows Cluster and started with SQL Server Management Studio’s New Availability Group Wizard, scripting out the steps along the way. This entire process took only a matter of minutes. The minimum required steps for configuring the cluster and getting a database into an Availability Group (AG) are very few. This process, however, is deceptively simple. What some don’t realize is that the majority of work required for setting up an AG needs to occur in the planning phase, before a server is even requisitioned. Let us examine the questions that you should ask before implementing an AG.

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Daniel Calbimonte

SQL Server Replications

November 30, 2014 by

Introduction

This article is for people who need to replicate the SQL Server Databases. SQL Server includes several types of replications to synchronize the databases across different SQL Servers.

Sometimes we need to replicate the data to have a Backup. Sometimes we need to synchronize Servers that are located in different cities or countries.

In this article, we will introduce you to the SQL Server Replication Theory and then we will show a step-by-step tutorial to replicate a Table using the Merge replication.

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Ivan Stankovic

What is SQL Server log shipping?

March 16, 2014 by

What is SQL Server log shipping?

SQL Server log shipping is a technique which involves two or more SQL Server instances and copying of a transaction log file from one SQL Server instance to another. The process of transferring the transaction log files and restoring is automated across the SQL Servers. As the process result there are two copies of the data on two separate locations Read more »
Ivan Stankovic

What is SQL Server database mirroring?

March 15, 2014 by
SQL Server database mirroring is a disaster recovery and high availability technique that involves two SQL Server instances on the same or different machines. One SQL Server instance acts as a primary instance called the principal, while the other is a mirrored instance called the mirror. In special cases, there can be a third SQL Server instance that acts as a witness Read more »
Ivan Stankovic

Top 10 articles on the SQL Server transaction log

February 13, 2014 by

Understanding Logging and Recovery in SQL Server

In “Understanding Logging and Recovery in SQL Server”, Paul S. Randal has given a complete overview of the transaction log. In four sections he explains: what is logging, what is recovery, how the transaction log works, and which recovery models are available. This article can be used as a starting point in understanding fundamentals of the transaction log and the logging process Read more »
Ivan Stankovic

A beginner’s guide to SQL Server transaction logs

February 11, 2014 by

What is a transaction log?

A transaction log is a file – integral part of every SQL Server database. It contains log records produced during the logging process in a SQL Server database. The transaction log is the most important component of a SQL Server database when it comes to the disaster recovery – however, it must be uncorrupted. After each database modification – transaction occurrence, a log record is written to the transaction log. All the changes are written sequentially Read more »