Reducing Run-time Execution in Query Optimization

Sampling - Based Query Execution Time Prediction and Query Re - Optimization

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Query Optimization for Parallel Execution

Parallel query processing has received a lot of attention in the database community because customer applications on databases are growing in size and complexity with an ever increasing demand for performance. The main objective of parallel query processing is to achieve speedup, scaleup and high throughput. Parallel machines are necessary for achieving the speedup, however eecient resource uti...

Query Optimization and Execution in Vectorwise MPP

Run-time Adaptation for Multi-Core Execution

Contention over shared resources is one of many variables affecting parallel performance on modern multi-core processors. The issue is of particular interest because it the primary factor limiting fully independent threads/processes which would otherwise showcase linear speedup with each additional core. Furthermore, addressing the problem is a non-trivial task. Shared-resource contention, whil...

Uncertainty Aware Query Execution Time Prediction

Predicting query execution time is a fundamental issue underlying many database management tasks. Existing predictors rely on information such as cardinality estimates and system performance constants that are difficult to know exactly. As a result, accurate prediction still remains elusive for many queries. However, existing predictors provide a single, point estimate of the true execution tim...