One of the recent tasks I undertook on configuring Transparent Data encryption (TDE) using asymmetric key protection with Azure Key Vault with Always On opened a different dimension on securing data for me. Even though it seems slightly complex, if you have the key details, the steps are in fact, really straight forward.
Read more »
With the latest versions of Azure SQL database, Microsoft has introduced a number of new mechanisms to help users and administrators better optimize their workload.
Automatic index management and Adaptive query processing provide us with the possibility to rely on the built-in intelligence mechanism that can automatically tune and improve the performance of our workload.
Read more »
When you perform a SQL Server Online Index Rebuild operation, introduced for the first time in SQL Server 2005, the index will not be taken down. But at a specific point, in which the new index new is built and switched from the old structure of the index, a special kind of lock, Schema Modification (SCH-M), will be granted. This lock may cause blocking if your database server is busy.
Read more »
This article is the last one of a series in which we discussed how to collect data about deadlocks so that we can not only monitor them but also build reports based on our collection results.
Read more »
The performance of a database is the most challenging and critical part of database optimization. The challenge every DBA faces is to identify the most resource-intensive databases. This article talks about the natively available features that can accomplish the task of getting the required details of the entire database at a granular level.
Read more »
When it comes to the monitoring of SQL Server system databases, the tempdb database is one of the most important for consideration, since it holds most of the internally created objects.
Read more »
In the previous article, on tracking database file storage usage How to track SQL Server database space usage with built-in functions and DMVs, I introduced some ideas and calculations for figuring out when your database is going to run out of headroom on the file system – hopefully in time to get an order in the works to increase that space!
Read more »
Indexing is key to efficient query execution. Determining what indexes are needed to satisfy production needs is often a game of cat and mouse in which we are forced to react to performance problems after they are brought to our attention. Being able to proactively monitor index needs and respond effectively before complaints are received can save us immense time while preventing costly performance messes.
Read more »
Managing indexes is a critical component of database maintenance but we often don’t think about the indicators behind the index maintenance operations. SQL Server 2017 (CTP 2.0) introduces a very useful index feature, to mitigate the administration overhead of index maintenance which we’ll review and discuss in this article.
Read more »
Locking is essential to successful SQL Server transactions processing and it is designed to allow SQL Server to work seamlessly in a multi-user environment. Locking is the way that SQL Server manages transaction concurrency. Essentially, locks are in-memory structures which have owners, types, and the hash of the resource that it should protect. A lock as an in-memory structure is 96 bytes in size.
Read more »
Indexing is key to efficient query execution. Knowing what indexes are unneeded, incorrectly used, or unused can allow us to reduce disk usage and improve write performance at little cost to your organization.
Read more »
Implementing a new database consists of various aspects like creating indexes, tuning stored procedures or installing new RAM etc. But among all of these items, performance stress testing plays a prominent role.
Read more »
Just like a book index, SQL Server index has a similar purpose, to provide faster searching, gathering and sorting of information from a database, without need to go through all of the objects over and over. Instead, an index provides the gateway between the table rows and query engine, in order to achieve better both database and query performance.
Read more »
In the previous article entitled “What are SQL Server deadlocks and how to monitor them“, we’ve seen how a deadlock can occur and which tools are available to DBA or developer to get simple or extended information about the conditions that lead a particular deadlock situation to occur.
Read more »
Every once in a while, SQL Server database administrators find themselves in disagreements with their application developer counterparts – particularly when it comes to some of the latter’s Transact SQL (T-SQL) developmental practices. One of my first observations when I joined my current employer is that almost all T-SQL scripts written by application developers uses the NOLOCK table hint. However, from the interactions that I have had with these esteemed developers it doesn’t seem like they understand how the NOLOCK table hint works. Furthermore, although they seem to be aware of a distinction between NOLOCK and the WITH NOLOCK table hint, they again do not seem to comprehend how the two differ from one another. In this article, I explore the internal workings of the NOLOCK table hint and examine the implications of omitting the WITH keyword.
Read more »
Slow running queries are one of the most common problems in every organization dealing with huge amounts of data. And the most challenging problem, in almost all the clients, I work with, is how to find the queries running slow and figuring out what is the actual cause behind the performance problem. Thankfully, the solution, in most cases, is simple.
Read more »
With Microsoft SQL Server, like all Microsoft products, you will enjoy experiencing new features and enhancements to the existing ones, when a new SQL Server version is launched. These SQL Server enhancements concentrate heavily in simplifying and speeding up the data retrieval without consuming excessive resources.
Read more »
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.
Read more »
As a DBA, I’ve been, more than, confronted with performance problems. Sometimes, poorly written code or lack of indexes will generate blocking conditions that we refer to as a“Deadlock”. Due to their nature and like any similar blocking situation, deadlocks can have a direct impact on user experience and the more they occur, the bigger the impact.
Read more »
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.
Read more »
Performance tuning is one of the most important and critical tasks that the SQL Server Database Administrator performs on a daily basis to keep a SQL Server running in a healthy state, by identifying the performance bottlenecks and fixing the main cause of these problems.
Read more »
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.
Read more »
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.
Read more »
The SQL Server Query Processing Engine is the most complex and sophisticated part of SQL Server. This engine has many responsibilities, but one of the most important parts is to design the query execution plan and execute it in a best and most efficient possible manner.
Read more »© Quest Software Inc. ALL RIGHTS RESERVED. | GDPR | Terms of Use | Privacy