US 2016/0078090 A1 · OPTIMIZING PARALLEL QUERIES USING INTERESTING DISTRIBUTIONS

Abstract

The present invention extends to methods, systems, and computer program products for optimizing parallel queries using interesting distributions. For each logical operator in an SQL server MEMO, in a top down manner from a root operator to the leaf operators, interesting distributions for the operators can be identified based on the properties of the operators. Identified interesting distributions can be propagated down to lower operators by annotating the lower operators with the interesting distributions. Thus, a SQL server MEMO can be annotated with interesting distributions propagated top down from root to leaf logical operators to generate an annotated SQL server MEMO. Parallel query plans can then be generated from the annotated SQL server MEMO in a bottom up manner from leaf operators to a root operator. Annotated interesting properties can be used to prune operators, thereby facilitating a more tractable search space for a parallel query plan.

Claims20

Dependent claims

A computer system, the computer system comprising:

one or more processors;
system memory;
and
a distribution identifier, using one of the one or more processors, configured to:
access a query plan search space for a query of a distributed database;
and
formulate an annotated query plan search space, including:
for a group of logical operators in the query plan search space, identify a distribution property indicating an interesting type of distribution relevant to the group, the distribution property identifying a column that data for a parent group of the group is distributed on;
and
annotate the group with the interesting type of distribution by attaching an indication of the identified column to the group to propagate the identified interesting type of distribution to the group for use in subsequent query plan pruning.

7 more elements

A method for use at a computer system, the computer system including one or more processors and system memory, a method for identifying and propagating interesting properties within a query plan search space, the method comprising:

accessing a query plan search space for a query of a distributed database;
and
formulating an annotated query plan search space by:
for a group of logical operators in the query plan search space, identifying a distribution property indicating an interesting type of distribution relevant to the group, the distribution property identifying a column that data for a parent group of the group is distributed on;
and
annotating the group with the interesting type of distribution by attaching an indication of the identified column to the group to propagate the identified interesting type of distribution to the group for use in subsequent query plan pruning.

3 more elements

Dependencies are inferred from the claim text.

Optimizing parallel queries using interesting distributions

Life of this patent

Optimizing parallel queries using interesting distributions

Life of this patent

Abstract

Claims20