I noticed that very few people understand how indexes work in SQL Server, especially Included Columns. Nevertheless, indexes are the great way to optimize queries. At first, I also did not get the idea of the included columns, but my experiments showed that they are very useful. (more…)
In this article, we are going to touch upon the topic of performance of table variables. In SQL Server, we can create variables that will operate as complete tables. Perhaps, other databases have the same capabilities, however, I used such variables only in MS SQL Server.
We continue to analyze what is happening on our MS SQL Server. In this article, we are going to explore how to retrieve information about user performance: who makes what, and how much resources are consumed.
I think the second part will be interesting for both database administrators and developers who need to understand what is wrong with the requests on the production server that used to work fine on the test server.
I’ve recently encountered a problem – SVN went down on ubuntu server. I develop for Windows and I do not have much experience with Linux. I googled the error — without success. The error turned out to be the most typical one (the server unexpectedly closed the connection) and does not indicate anything. Therefore, it was necessary to go deeper and analyze logs/settings/rights/etc.
Finally, I figured out the mistake and found everything I needed, but I spent a lot of time. After solving this problem, I thought about how to reduce the uselessly spent hours and decided to write an article that will help people quickly get the understanding of the unfamiliar software.
There is an information system that I administer. The system consists of the following components:
1. MS SQL Server database
2. Server application
3. Client applications
These information systems are installed on several objects. The information system is used actively 24 hours a day by 2 to 20 users at once on each object. Therefore, you cannot perform routine maintenance all at once. So, I have to «spread» SQL Server index defragmentation throughout the day, rather than defragmenting all the necessary fragmented indexes at one stroke. This applies to other operations as well.
In this post, I’d like to take a brief look at the Query Performance Insight — SQL Azure tool which will help you to identify the most expensive queries in your database.
Query Performance Insights was announced in early October 2015. To understand what it is, let’s think about how do you usually learn that the database performance got down? Probably, you are receiving emails from your clients or it takes an hour to create a weekly report instead of a several minutes, or maybe, your application starts throwing exceptions. (more…)