Like all database systems, the SQL Server performs extremely complex tasks like
- Memory management.
- Optimum CPU utilization.
- Query optimization.
- Execution planning, etc.
at a lightning fast speed.This article deals with what takes over when you press that F5 key on you keyboard.
The diagram above gives an overview of what the SQL Server architecture looks like. There are 3 important items here.
- Database Engine: Performs the storage and query processing tasks.
- SQL Operating System: Woks on I/O and other higher level management tasks.
- Interfaces: The External Protocols and SQL Operating System API connect the dots.
The database engine is the heart of MSSQL Server. Think of it as the engine of a motorcycle, it is the part where the real stuff happens. It contains 2 major components.
- Query Processor: Parses optimizes and executes the query.
- Storage Engine: Manages buffer and access methods.
Going with motorcycle analogy, the SQL Operating System API and External protocols are the wires and dials. They connect the speedometer to the front wheel, show you the speed. This speed can then be reduced or increased using the accelerator. They simply provide ways to connect internal and external components together and manipulate the operations.
The SQL OS is everything else, it is the frame, the seat, the tires. It is the structure that gets everything else going.You can have an engine and some wires, but unless you have the frame they will never mate.
