Parallel Query Execution in PolarDB by Oystein Grovlen

17 March 2019 11:30, Training Room 2-1

The upcoming version of PolarDB will support parallel execution of an SQL query. In this presentation we will show how query execution times may be significantly improved by using multiple threads to scan a table or index in parallel. Each thread will be able to do filtering and aggregation in order to reduce the amount of data to be processed by the query coordinator. We will discuss which type of queries will benefit from this feature, and present results that shows performance and scalability characteristics. We will also show how to control the degree of parallelism for a query and discuss other aspects of tuning of parallel queries.