Get valuable Virtual Log File (VLF) information for all your databases log files

I had this problem where I needed to gather Transaction Log information on multiple databases and check for valuable statistics on them. Running the command [DBCC Loginfo] brings back a number of rows for each Virtual Log File (VLF) in your Log File. It is really hard to do anything useful with that information on a larger scale. Each row returned gives you an estimate for the number of VLFs per Log File. Sure you could use the internal (and hidden) system stored procedure sp_msforeachdb to get the information for all database but it looks horrible. Here try it out for yourself before you read the rest of the post:

exec sp_MSforeachdb 'Use [?] select db_name(); DBCC LogInfo'

So why not make it better? That’s what I thought to myself, and I have recently been playing with storing DBCC command output to tables for analysis. I’ve put some together some code that allows you to capture the output of DBCC LogInfo into a Temp Table and then get some interesting information about the number of VLFs per database and other valuable information; see the comments for more information. Just by storing some of this data temporarily, I was able to write queries against it and discovered a major inconsistency in the size of my VLFs in a Log File that could potentially cause performance issues.

Feel free to create a permanent table for this data and run it on a regular basis to get an understanding of what your system is doing for troubleshooting. I also commented out the date field since I deemed it unnecessary, but if you’re looking for trending it maybe a good option to have that additional data.

 

[SQL Snacks Video] Performance Tuning 103 – T-Logs and VLFs

Finally the arrival of Part 3 of my SQL Snack Pack on Performance Tuning! The series is dedicated to help beginners understand how to start performance tuning with SQL Server. The first video was about performing a baseline using the PAL tool.I would highly recommend you review that video as well as my SQL Snack on Instant File Initialization. Also, if you missed part two from yesterday you can review it here.

If you are still interested in learning more about Performance tuning with SQL Server, I will be giving an hour long presentation with the PASS DBA Fundamentals Virtual Chapter on January 6, 2015 (11 am Central Time/Noon Eastern Time).  For more information please visit http://dbafundamentals.sqlpass.org/ and join PASS for a great way to learn more about SQL Server.

Code from Demo below:

 

[SQL Snacks Video] Performance Tuning 102 – Files, FileGroups, and TempDB

Finally the arrival of Part 2 of my SQL Snack Pack on Performance Tuning! The series is dedicated to help beginners understand how to start performance tuning with SQL Server. The first video was about performing a baseline using the PAL tool.I would highly recommend you review that video as well as my SQL Snack on Instant File Initialization. This second video discusses the importance of properly sizing Data files, placement, and how the Proportional Fill-Algorithm works for data insertion. I’m hoping you get some last minute Performance tuning in before 2015 and so I will be posting the third video within the next 24 hours.

Code from Demo below:

 

[SQL Snacks Video] Performance Tuning 101 – Baseline with PAL Tools

Welcome to Part 1 of my SQL Snack Pack on Performance Tuning! The series is dedicated to help beginners understand how to start performance tuning with SQL Server. This first video describes how to setup a baseline for your system using the PAL tools. It is essential to get a baseline before you start performance tuning so that you can determine how effective the efforts done in trying to tune your SQL Server have been.  The PAL tools at first look a little intimidating but they are really very easy to use and extremely helpful for performance analysis. Enjoy and happy baselining!

A special thanks to Edgardo Valdez for showing me the how to use this tool.

Link to download PAL Tools and Prerequisites: https://pal.codeplex.com/

 

[SQL Snacks Video] SQL Server Table Partitioning 103

Welcome back for part 3 of my SQL Snack Pack on Table Partitioning! If you have not watched the first two videos, I would highly encourage you to do so.

 

[SQL Snacks Video] SQL Server Table Partitioning 102

Welcome back for part 2 of my SQL Snack Pack on Table Partitioning! If you have not watched the first video, I would highly encourage you to do so.

 

[SQL Snacks Video] SQL Server Table Partitioning 101

I hope you’re hungry for another SQL Snack! In fact, this will be one of a series of snacks (dare I call it a SQL Snack pack?). Table partitioning is a fantastic feature that is easy to learn and can significantly improve your OLTP and Data-warehouse environments. It can be a little intimidating because it is tricky to get started with, but once you get the basics down you’ll realize it’s pretty straight forward and a very useful feature to have.  I will be providing the code and outline for each of the SQL Snacks related to table partitioning so that you have a chance to practice on your own.  Happy partitioning!

 

[SQL Snacks Video] The Basics of Joins

This is a special edition for SQL Snacks.  It is one (of many hopefully) SQL Snacks that has been recorded with the intention of fulfilling a request by a SQL community member looking to learn more about SQL Server.  It is straight forward, very basic, beginner level information about Joins with a few examples.

 

[SQL Snacks Video] The What, Why, and How of Instant File Initialization with SQL Server

Instant File Initialization (IFI) is an interesting topic with regards to how SQL Server works with storage. It is an easy feature to turn on and can improve the performance of your server; specifically with creation and growth of data files including TempDB rebuilds with SQL Server restarts.  There is a slight security risk where a professional data thief could potentially recover bits of data that have not been over written since IFI was turned on, but the chances of that happening are slim.  Plus, if they have physical access to the hard drives on your server, you will have bigger problems to fix.

So without further ado here is the next delicious SQL Snack for Instant File Initialization:

 

[SQL Snacks Video] Importance of COPY_ONLY Backups

There are many features/options we sometimes overlook and then wonder later what went wrong. The COPY_ONLY option with backups is one that I felt is important to highlight to SQL Server DBAs. This backup is independent backup that is not part of the regular cycled backups that you perform; hint if you’re not performing regular backups please get up and schedule them NOW! Sorry for yelling 🙂

Using this option when doing backups allows you to take backups that do not interfere with your regularly scheduled backups in order to move them off to a QA, Development, or Staging area where you can test against that database or fix bugs without interrupting your production environment. Many times, I have seen that off-cycle backups are taken which become part of the backup set and then are deleted. This can cause negative consequences when doing restores as I will demonstrate in today’s SQL Snack:

Code is provided below if you would like to test it yourself. Please watch the video in order to understand how to test this yourself:

 

[SQL Snacks Video] Tail Log Backup and Recovery Demo

In December 2013 I presented at a SQL Saturday event in Washington DC. My presentation was about Backup and Recovery Fundamentals which I had done before for the PASS DBA Fundamentals Virtual Chapter. This time around, I decided to add a Tail Log (Active Log) Backup and Recovery demo to enhance my Presentation. The presentation went quite well, and so I’ve decided to put a short video together to demonstrate how to do a Tail Log Backup and Recovery.

***Make sure you change the backup, database, and log file paths to match your configuration***

Code for demo below.

 

[SQL Snacks Video] Introducing SQL Snacks! A healthy alternative to boring learning!

To snack lovers every where now you can consume SQL Learning the same way, in Snack Size!  Introducing the new way to snack with 0 calories intake, a simple solution to your learning cravings and available 24/7 from the click of a button!

Late last year I introduced my YouTube Channel with a short video on Hyper-V followed by a 10 hour series of teaching SQL Server in Arabic.  This year, I hope to continue with those projects and in addition to that add to my newest delicious invention, the SQL Snack.  The idea of this video series is to provide short videos to teach SQL Server content; and other technologies relevant to SQL Professionals on a daily basis.  This allows for people to grab a snack and enjoy a short learning experience instead of having to sit down for a long drawn out lecture.  Real snack is optional and not provided by me… sorry!

Below is the SQLSnacks Playlist you can also access it at the top menu by hovering over “Videos” and selecting it.

Please enjoy and please feel free to suggest topics you would like to see in the comments and I will try to do my best to accommodate your requests.