
T-SQL commands performance comparison – NOT IN vs SQL NOT EXISTS vs SQL LEFT JOIN vs SQL EXCEPT
September 22, 2017This articles gives you a performance comparison for NOT IN, SQL Not Exists, SQL LEFT JOIN and SQL EXCEPT.
This articles gives you a performance comparison for NOT IN, SQL Not Exists, SQL LEFT JOIN and SQL EXCEPT.
SQL Server Maintenance Plans is a SQL Server Management Studio built-in feature that helps in creating a workflow of variant database administration tasks, which can be run automatically using a predefined schedule or manually triggered by the user. SQL Server Maintenance Plans allow you to use typical database maintenance tasks or customize your own task […]
It is a common misconception that you need real production data, or production like data, to effectively tune queries in SQL Server. I am going to explain how you can compile the same execution plans as what your production environment would compile, so that you can tune them in a non-production environment, gaining these benefits.
Today’s businesses work with huge volumes of data. Sometimes, understanding the granularity of the data is helpful in data administration. Understanding the granularity poses unique challenges though and the database administrator needs to balance the key business and technical metrics of the environment. One of the key technical metrics is disk space estimation, which is […]
Introduction Azure Cosmos DB is a low-latency, high throughput, globally distributed, a multi-model database which can scale within minutes and offers 5 consistency options to let you decide how to deal with the CAP theorem. Azure Cosmos DB used to be known as Document DB, but since additional features were added it has now morphed […]
In SQL Server, it`s not always required to fully understand the internal structure, especially for performance and optimization, if the database design is good, because SQL Server is a very powerful Relational Database and, as such, it has many inbuilt optimization processes which assure a response to the users as fast as possible. But it […]
Introduction In most cases, we will use clustered and non-clustered indexes to help a query go faster, but these kinds of indexes have their own limitations and cannot be used for fast text lookup. For instance, a LIKE operator will lead SQL Server to scan the whole table in order to pick up values that […]
As discussed in the article All about latches in SQL Server, spinlocks are also a special form of locks that SQL Server uses to protect data. Spinlocks are lightweight objects used by the SQL Server Operating System (SQLOS) to protect data structure access. To understand, properly, the difference between latches and spinlocks and why the […]
In this article, a demonstration of the tabular model will try to related multidimensional cube design to the path forward Microsoft is giving used s with new versions of Analysis Services. Even though the descriptive names are changing, the tabular model still accomplishes the centralized business rules multidimensional cubes gave the business intelligence world. This […]
Linked servers allow SQL Server access to data from a remote data source. A remote data source can be another SQL Server instance or other data sources such MySQL, Access databases, Oracle, Excel workbooks, text files etc.
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.
Do you want to make your deployments risk free? Do you want to deliver business values to your customers faster? Do you want to increase the efficiency of your Team? Are your application and database deployment separate processes? Do you encounter issues while deploying your database changes? Is your database slowing you down?
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.
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 […]
Whether you’ve been using PowerBI for a while or you’re just getting started with it, chances are you’ll want to source at least some of your data from on-premises systems. Be that SQL server databases, Oracle, SSAS etc. The same process even applies if you’re sourcing from AWS which I’ll go into in more detail […]
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 […]
Overview 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 […]
This article is the second part of the Nested Loop Join Series. In the first part, Introduction of Nested Loop Join, we gave a brief introduction to Native, Indexed and Temporary Index Nested Loop Joins along with CPU cost details.
Introduction 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 […]
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 […]
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.
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 […]
It was a paradigm shift in December 2016, when Microsoft made their SQL Server database available for Linux; it was the first time in history that Microsoft ever designed SQL Server to run on a non-Windows operating system. SQL Server vNext was released for public preview so the user community could test and deploy SQL […]
A relational database system uses SQL as the language for querying and maintaining databases. To see the data of two or more tables together, we need to join the tables; the joining can be further categorized into INNER JOIN, LEFT OUTER JOIN, RIGHT OUTER JOIN, FULL OUTER JOIN, and CROSS JOIN. All these types of […]
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 […]
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