Timothy Smith

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Tim manages hundreds of SQL Server and MongoDB instances, and focuses primarily on designing the appropriate architecture for the business model.

He has spent a decade working in FinTech, along with a few years in BioTech and Energy Tech.He hosts the West Texas SQL Server Users' Group, as well as teaches courses and writes articles on SQL Server, ETL, and PowerShell.

In his free time, he is a contributor to the decentralized financial industry.

View all posts by Timothy Smith

Useful DBCC log commands

June 1, 2016 by Timothy Smith

Background

When we’re architecting or troubleshooting issues in an environment, understanding how the log is set up and its history helps us identify if improving it will carry significant impacts overall. We have some built in tools that we can use, such as DBCC LOGINFO and DBCC SQLPERF and in this tip we look at how we can use them when we’re debugging issues, designing our logs for scale, or monitoring our current setup. We also look at some ways we can retain the information these provide so that we can use this for historic measurements and benchmarking, as well as using them for potentially alerting.

Monitoring changes in SQL Server using change data capture

May 27, 2016 by Timothy Smith

Background

In multi-user environments, changes may occur frequently to the architecture, data, or overall structure that creates work for other users. In this series, we look at some ways that we can track changes on the data and architecture layer for pin-pointing times, changes, and using the information for alerting, if changes should be kept to a minimum. SQL Server comes with some built-in tools that allow us to monitor changes, and depending on the architecture, we can create tools that allow us also to monitor and identify changes near the time that they occur.

Some replication architecture errors and their resolutions

May 16, 2016 by Timothy Smith

Background

From time to time, I’ve run into replication issues in inherited environments that I did not architect and some of these environments experienced errors in replication because of how it was constructed from the beginning. In this tip, we look at some of the basics in replication architecture and then at solving some of these problems. Some of the replication issues I’ve seen are caused by misunderstanding what is impossible and possible with replication.

Troubleshooting some waits issues

May 10, 2016 by Timothy Smith

Background

On occasion, I’ll see waits that exceed what I expect well above normal and a few of them have some architecture and standards to consider following when troubleshooting, though like most waits’ issues, there can be other underlying factors that are happening as well. In this article, I investigate the three waits ASYNC_NETWORK_IO and WRITELOG. In general, waits vary by environment and server, so before reading this article an immediate question to ask is, “Do you know what’s normal for yours?” When a wait suddenly spikes, or if the architecture is designed in a manner that should prevent a specific wait from consuming time, and yet you see that the wait does, I would be concerned. In addition, because applications and environments differ by architecture, you may want to consider other troubleshooting steps, as these may not apply to your situations.

How to build better alerting

May 4, 2016 by Timothy Smith

Background

One of the most popular complaints from developers to DBAs involves alerting, whether from third party tools or alerting built by other developers or DBAs in the environment. Building or using alerts for important applications, data layers, or processes within a SQL Server environment offer everyone benefits, but can become noisy if they’re architected poorly, or the purpose isn’t considered. In this article, we look at considerations for building effective alerts that tell us when something is wrong without creating situations where we learn to disregard them. We want to make sure that we respond when we need to, and not always be on high alert when there is no issue.

Understanding the distribution scale of transactional and snapshot replication

January 25, 2016 by Timothy Smith

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.