Quicksel: Quick selectivity learning with mixture models

Y Park, S Zhong, B Mozafari - Proceedings of the 2020 ACM SIGMOD …, 2020 - dl.acm.org
Estimating the selectivity of a query is a key step in almost any cost-based query optimizer.
Most of today's databases rely on histograms or samples that are periodically refreshed by …

Main memory database systems

F Faerber, A Kemper, PÅ Larson… - … and Trends® in …, 2017 - nowpublishers.com
This article provides an overview of recent developments in mainmemory database systems.
With growing memory sizes and memory prices dropping by a factor of 10 every 5 years …

Efficiently approximating selectivity functions using low overhead regression models

A Dutt, C Wang, V Narasayya… - Proceedings of the VLDB …, 2020 - dl.acm.org
Today's query optimizers use fast selectivity estimation techniques but are known to be
susceptible to large estimation errors. Recent work on supervised learned models for …

Improved selectivity estimation by combining knowledge from sampling and synopses

M Müller, G Moerkotte, O Kolb - Proceedings of the VLDB Endowment, 2018 - dl.acm.org
Estimating selectivities remains a critical task in query processing. Optimizers rely on the
accuracy of selectivities when generating execution plans and, in approximate query …

[PDF][PDF] Enhanced Featurization of Queries with Mixed Combinations of Predicates for ML-based Cardinality Estimation.

M Müller, L Woltmann, W Lehner - EDBT, 2023 - openproceedings.org
Background. For some years now, Machine Learning (ML) has been applied to the
cardinality estimation problem [8, 12, 32, 33]. In general, ML means arbitrary function …

Methods and systems for one dimensional heterogeneous histograms

N May, G Moerkotte, A Boehm - US Patent 9,189,520, 2015 - Google Patents
BACKGROUND Query optimization depends in large part on efficient and accurate
cardinality estimates of intermediate results and the plan for the order of a sequence or set of …

Statisticum: data statistics management in SAP HANA

A Nica, R Sherkat, M Andrei, X Cheng… - Proceedings of the …, 2017 - dl.acm.org
We introduce a new concept of leveraging traditional data statistics as dynamic data integrity
constraints. These data statistics produce transient database constraints, which are valid as …

Cardinality estimation for database query planning

G Moerkotte, A Boehm, N May - US Patent 10,534,775, 2020 - Google Patents
(57) ABSTRACT A system for cardinality estimation for database query planning is provided.
In some implementations, the system performs operations comprising selecting a subset of …

Boosting data filtering on columnar encoding with SIMD

H Jiang, AJ Elmore - Proceedings of the 14th International Workshop on …, 2018 - dl.acm.org
In columnar databases, data is generally stored in an encoded format to save storage space
and reduce I/O. Popular encoding schemes include dictionary encoding, delta encoding, run …

Small selectivities matter: Lifting the burden of empty samples

A Hertzschuch, G Moerkotte, W Lehner, N May… - Proceedings of the …, 2021 - dl.acm.org
Every year more and more advanced approaches to cardinality estimation are published,
using learned models or other data and workload specific synopses. In contrast, the majority …