Execution plans

Esat Erkec
Comparison of the Merge Join vs Hash Match Join

Query Optimization Myths

March 23, 2021 by

In this article, we will talk about two query optimization myths and these myths can be changed according to the characteristics of the queries. Every query can exhibit different behaviors according to data distribution, SQL Server version, database settings, and other tons of parameters therefore the fixed ideas may not help to overcome the query performance issues. In the next part of the article, we will focus on the following most known discourse:

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Esat Erkec
How we can read a query plan

How to read an execution plan with all details

January 28, 2021 by

In this article, we will discuss how to read the SQL Server execution plan (query plan) with all aspects through an example, so we will gain some practical experience that helps to solve query performance issues. Interpreting query plans correctly is the first and major principle to troubleshoot query performance issues. When we try to find an answer to the “why is this query running slow?” question, the best starting point would be to analyze the query plan.

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Esat Erkec
Trivial query plans and contradiction detection

Explore the secrets of SQL Server execution plans

December 10, 2020 by

The SQL Server execution plan (query plan) is a set of instructions that describes which process steps are performed while a query is executed by the database engine. The query plans are generated by the query optimizer and its essential goal is to generate the most efficient (optimum) and economical query plan. Some query plans that are created by the query optimizer contain some interesting characteristics. In this article, we will go into details of these interesting query plans.

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Ahmad Yaseen

Saving your SQL Execution Plan

November 28, 2018 by

In the previous articles of this series (see the index at bottom), we discussed the characteristics of the SQL Execution Plan from multiple aspects, that include the way the SQL Execution Plan is generated by the SQL Server Query Optimizer internally, what are the different types of plans, how to identify and analyze the different components and operators of the Execution Plans, how to work with the plans using different tools and finally, tuning the performance of simple and complex T-SQL queries using the Execution Plans. In this, the last article of this series, but not the least, we will discuss where the Execution plan is stored and how to save it for future use.

Bojan Petrovic

SQL index overview and strategy

November 27, 2018 by

A SQL index is used to retrieve data from a database very fast. Indexing a table or view is, without a doubt, one of the best ways to improve the performance of queries and applications.

A SQL index is a quick lookup table for finding records users need to search frequently. An index is small, fast, and optimized for quick lookups. It is very useful for connecting the relational tables and searching large tables.

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Ahmad Yaseen

Using the SQL Execution Plan for Query Performance Tuning

November 23, 2018 by

In the previous articles of this series (see the index at bottom), we went through many aspects of the SQL Execution Plan, where we discussed how the Execution Plan is generated internally, the different types of plans, the main components and operators and how to read and analyze the plans that are generated using different tools. In this article, we will show how we can use an Execution Plan in tuning the performance of T-SQL queries.

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