Execution plans

Ahmad Yaseen

SQL Server Execution Plan Operators – Part 1

September 12, 2018 by

In the previous articles of this series, SQL Server Execution Plans overview , SQL Server Execution Plans types and How to Analyze SQL Execution Plan Graphical Components, we discussed the steps that are performed by the SQL Server Relational Engine to generate the Execution Plan of a submitted query and the steps performed by the SQL Server Storage Engine to retrieve the requested data or perform the requested modification operation.

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Ahmad Yaseen

How to Analyze SQL Execution Plan Graphical Components

September 7, 2018 by

In the previous articles of this series, SQL Server Execution Plans overview and SQL Server Execution Plans types we went through the different stages that the submitted SQL Server query followed and how it processed by the SQL Server Relational Engine that generates the Execution Plan and the SQL Server Storage Engine that performs the requested data retrieval or modification operation. In addition, we described deeply the different types and formats of the SQL Server Execution Plans that can be used for queries performance troubleshooting purposes. In this article, we will discuss the graphical query plan components and how to analyze it.

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James Rhoat

Performance troubleshooting when the query plan from the application is different than SSMS

August 24, 2018 by

Troubleshooting performance issues in a database is one of the main jobs of DBAs and by now most can trace the problem back to a query which is either running to slow or is causing a blocking issue on a key table. However, what is often not known is why this doesn’t cause problems in SSMS or why you don’t get the same query plan as what is inside the app. For example, in your extended event trace you see the query running longer from the application when compared to SSMS.

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Ahmad Yaseen

SQL Server Execution Plans types

July 23, 2018 by

In the previous article, we described, in detail, the different stages that a submitted SQL Server query goes through and how it processed by the SQL Server Relational Engine. The SQL Server Relational Engine generates the Execution Plan and the SQL Server Storage Engine performs the requested data retrieval or modification process. In this article, we will discuss the different types and formats for SQL Server Execution Plans.

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Aamir Syed

Use cases for Query Store in SQL Server

July 18, 2018 by

Query store was introduced in SQL Server 2016. It is often referred to as a “flight data recorder” for SQL Server. Its main function is that it captures the history of executed queries as well as certain statistics and execution plans. Furthermore, the data is persistent, unlike the plan cache in which the information is cleared upon a server restart or reboot. You can customize, within Query Store, how much and how long the query store can hold the data.

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Esat Erkec

Main Concepts of SELECT operators in SQL Server execution plans

July 9, 2018 by

One of the main responsibilities of a database administrator is query tuning and troubleshooting query performance. In this context, SQL Server offers several tools to assist. But among them, query execution plans are essential for query optimization because they include all of the vital information about the query execution process. At the same time as it provides this valuable information “under the hood”, SQL Server creates a graphical description of the execution plan. Read more »

Ahmad Yaseen

SQL Server Execution Plans overview

July 4, 2018 by

In this series of articles, we will navigate the SQL Server Execution Plan ocean, starting from defining the concept of the Execution Plans, walking through the types, components and operators of Execution Plans analyze execution plans and we’ll finish with how to save and administrate the Execution Plans.

When you submit a T-SQL query, you tell the SQL Server Engine what you want, but without specifying how to do it for you. Between submitting the T-SQL query to the SQL Server Database Engine and returning the query result to the end user, the SQL Server Engine will perform four internal query processing operations, to convert the query into a format that can be used by the SQL Server Storage Engine easily use to retrieve the requested data, using the processes assigned to the SQL Engine from the Operating System to work on the submitted query.

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