Parallel Query Processing in SQL Server
Agenda
How Parallel Query works?
Parallel Query Plan – Exchanges
Parallel Query Plan – Partition and Redistribute types
Demo – Query Plan
Controlling Degree of Parallelism
SQL Server 7.0 (1998)
SQL Server 2000
SQL Server 2005
SQL Server 2008
What is Apollo in SQL 11?
Batch Mode: Performance Gains
Outline of the next slides
Encoding and Compression
New Iterator Model
Batch Segments
Efficient Processing
Better Parallelism
Batch Operations
When Batch Processing is Used
Memory Requirements
References

SQL Server 7.0 (1998)

First Release 1998 – SQL Server 7.0
Parallelism from “inside” through “partitioning on the flight” (most of competing products required data partitioning to exploit query parallelism)
Introduce parallelism operators (3 types of Exchanges)
Parallel Page Supplier
Exchange operators added into the query plan at the end of the optimization
Costing challenge: parallel plans seem to be always more expensive