Exploiting self-monitoring sample views for cardinality estimation

Good cardinality estimates are critical for generating good execution plans during query optimization. Complex predicates, correlations between columns, and user-defined functions are extremely hard to handle when using the traditional histogram approach. This demo illustrates the use of sample views for cardinality estimations as prototyped in Microsoft SQL Server. We show the creation of sample views, discuss how they are exploited during query optimization, and explain their potential effect on query plans. In addition, we also show our implementation of maintenance policies using statistical quality control techniques based on query feedback. Categories and Subject Descriptors H.2.4 [Database Management]: System--Query Processing General Terms Algorithms, performance Keywords Query optimization, cardinality estimation, sample views, sequential sampling, statistical quality control

• Type: Conference
• Year: 2007
• Where: SIGMOD
• Authors: Jingren Zhou, Per-Åke Larson, Peter Zabback, Wolfgang Lehner
• Keywords: Cardinality Estimations, Database, Keywords Query Optimization, Query Plans, SIGMOD 2007