Performance Tuning


SQL Server 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 SQL Server

Data Pages and Extents in SQL Server and how data is stored in SQL Server. Data records are physically stored in 8kb data pages on the hard drive.


SQL Query Processing

How SQL Queries are processed by the Relational Engine. Parsing, Resolving, Optimizing, Compiling, and Executing to return SQL Sets.


What are Locks?

What is a Lock? What is the process that transactions use to lock records to provide transaction isolation.


Transactions and Errors

SQL Transaction and Error Handling? What is the difference between Auto-Commit and Explicit Transactions and how transaction effect Errors and Exception Handling?


What are Transactions?

The ACID properties of SQL Transactions, What are the different ACID properties of a transaction how they ensure that data is Atomic, Consistent, Isolated, and Durable.