The MS SQL Server is often used to run complex applications that are used simultaneously by different users. At times you may experience a scenario where a query run on the database simply takes a way long amount of time to execute. If many large queries get in the queue, you have a situation where the application may seem unresponsive. Let’s look at the reason behind queries getting delayed and resolving the possible issues.
A Large Query get assigned to numerous cores
When you are running a large query, the SQL Server application can assign it to multiple cores. While in theory it looks great, distributing the workload to more than 8 cores is not advised. To resolve such a scenario you need to set the Maxdop to at most 8 cores.
Badly Written Queries that make large Logical or Physical Reads
At times the issue can simply be in the way the query has been created. If a query has to go through a lot of data and make large logical or physical reads, especially when it is called with frequency, it would make the whole application slow. Ideally you should analyze the queries and get the SQL programmer to rework them if needed.
Issue with Missing Indexes
In the SQL Server application, the query optimizer is responsible for generating a query plan that focuses on the most relevant indexes needed for a specific filter condition. Now if these appropriate indexes are not present the query plan created in not ideal and can cause delays. To resolve the issue you can take the help of Missing Index feature and take a look at suggested ideal indexes and if needed create them to speed up your queries by a significant degree. Typically this feature is available by default and you would find detailed reference material on Microsoft’s support site on using it. It is important to note that all missing index related information gets immediately removed incase the SQL Server application gets restarted.
SQL Errors should not be ignored Even if they seem trivial
At times if you receive an error message which you believe is trivial like not enough disk space, it is still best not to ignore them. Ideally you should ensure regular backup of your SQL data and put in place a recovery strategy that considers a sql recovery tool like the cutting edge DataNumen SQL Recovery in its plan. In the unfortunate event of an Outlook crash the application can swing into action and make sure that all your records are retrieved in pristine order. It is equipped to trace out all data structures including triggers or queries that you have saved in the application without any hassles. Last but not the least; in case of an inadvertent delete operation that led to the removal of a valuable record, the tool can be used to bring back the deleted data set.
Alan Chen is President & Chairman of DataNumen, Inc., which is the world leader in data recovery technologies, including access recovery and sql recovery software products. For more information visit https://www.datanumen.com/