Opportunities for Query Optimization
Optimize your SQL Server queries for maximum performance. Learn how to troubleshoot query plans and identify optimization opportunities.
Performance Tuning
Query Optimizer Phases
The SQL Server Query Optimizer uses cost-based optimization to create an execution plan with the least cost.
The SQL Server Database Engine
The three parts of the SQL Server database engine with a focus on how the SQL Server Operating System (SQLOS) component manages resources.
Troubleshooting Waiting Tasks
In this post, we will discuss Dynamic Management Objects (DMO’s) used to troubleshoot for Waiting Tasks in SQL Server.
Task Execution Model
How the SQLOS manages worker threads in the SQL Server Execution Model and the different wait queues in SQL Server to manage threads used by the CPU.
Execution Plans – Table Operators
How to read Heap and Clustered Index table operators in a SQL Server Execution Plan. One way of determining if a table is structured as a Heap or a Clustered Index is to look at the table operators from the Execution Plan.
Table Structures in SQL Server
Heaps vs Clustered Indexes and how tables are structured and data is stored in SQL Server. Data rows from a table are stored in the data pages in either an unsorted order (Heap) or a sort order (Clustered Index).
How Data is Stored in Data Pages
Data Pages and Extents in SQL Server and how data is stored in SQL Server. Data records are physically stored in 8kb data pages.
SQL Query Processing
How SQL Queries are processed by the Relational Engine. Parsing, Resolving, Optimizing, Compiling, and Executing to return SQL Sets.
Concurrency: Phantom Reads
A closer look at the Serializable Transaction Isolation Level and how it could prevent Phantom Reads concurrency issues in SQL Server.