Package org.apache.calcite.materialize

Class LatticeSuggester

java.lang.Object

org.apache.calcite.materialize.LatticeSuggester

public class LatticeSuggester
extends java.lang.Object

Algorithm that suggests a set of lattices.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
private static class	LatticeSuggester.BaseColRef	Reference to a base column.
private static class	LatticeSuggester.ColRef	Column reference.
private static class	LatticeSuggester.DerivedColRef	Reference to a derived column (that is, an expression).
(package private) static class	LatticeSuggester.Frame	Information about the parent of fields from a relational expression.
private static class	LatticeSuggester.Hop	A hop is a join condition.
private static class	LatticeSuggester.MutableMeasure	An aggregate call.
private static class	LatticeSuggester.Query	Holds state for a particular query graph.
private static class	LatticeSuggester.StepRef	Use of a step within a query.
private static class	LatticeSuggester.TableRef	Use of a table within a query.

Field Summary

Fields

Modifier and Type	Field	Description
private boolean	evolve	Whether to try to extend an existing lattice when adding a lattice.
(package private) java.util.Map<java.lang.String,Lattice>	latticeMap	Lattices, indexed by digest.
private java.util.Map<Lattice,Lattice>	obsoleteLatticeMap	Lattices that have been made obsolete.
private static HepProgram	PROGRAM
(package private) LatticeSpace	space

Constructor Summary

Constructors

Constructor	Description
LatticeSuggester(FrameworkConfig config)	Creates a LatticeSuggester.

Method Summary

Modifier and Type	Method	Description
java.util.List<Lattice>	addQuery(RelNode r)	Adds a query.
private static java.lang.String	deriveAlias(LatticeSuggester.MutableMeasure measure, LatticeSuggester.DerivedColRef derivedColRef)	Derives the alias of an expression that is the argument to a measure.
private Lattice	findMatch(Lattice lattice, MutableNode mutableNode)	Returns the best match for a lattice.
private LatticeSuggester.Frame	frame(LatticeSuggester.Query q, RelNode r)
java.util.Set<Lattice>	getLatticeSet()	Returns the minimal set of lattices necessary to cover all of the queries seen.
private java.util.function.Function<Lattice.Column,Lattice.Column>	mapper(Lattice lattice, Lattice.Builder builder)
private int	matchQuality(Lattice lattice, Lattice target)
private static <E> java.util.Set<E>	minus(java.util.Collection<E> c, java.util.Collection<E> c2)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

space

final LatticeSpace space

PROGRAM

private static final HepProgram PROGRAM

latticeMap

final java.util.Map<java.lang.String,Lattice> latticeMap

Lattices, indexed by digest. Uses LinkedHashMap for determinacy.

obsoleteLatticeMap

private final java.util.Map<Lattice,Lattice> obsoleteLatticeMap

Lattices that have been made obsolete. Key is the obsolete lattice, value is the lattice that superseded it.

evolve

private final boolean evolve

Whether to try to extend an existing lattice when adding a lattice.

Constructor Detail

LatticeSuggester

public LatticeSuggester(FrameworkConfig config)

Creates a LatticeSuggester.

Method Detail

getLatticeSet

public java.util.Set<Lattice> getLatticeSet()

Returns the minimal set of lattices necessary to cover all of the queries seen. Any lattices that are subsumed by other lattices are not included.

addQuery

public java.util.List<Lattice> addQuery(RelNode r)

Adds a query.

It may fit within an existing lattice (or lattices). Or it may need a new lattice, or an extension to an existing lattice.

Parameters:

r - Relational expression for a query

Returns:

A list of join graphs: usually 1; more if the query contains a cartesian product; zero if the query graph is cyclic

deriveAlias

private static java.lang.String deriveAlias(LatticeSuggester.MutableMeasure measure,
                                            LatticeSuggester.DerivedColRef derivedColRef)

Derives the alias of an expression that is the argument to a measure.

For example, if the measure is called "sum_profit" and the aggregate function is "sum", returns "profit".

findMatch

private Lattice findMatch(Lattice lattice,
                          MutableNode mutableNode)

Returns the best match for a lattice. If no match, registers the lattice and returns it. Never returns null.

mapper

private java.util.function.Function<Lattice.Column,Lattice.Column> mapper(Lattice lattice,
                                                                                Lattice.Builder builder)

matchQuality

private int matchQuality(Lattice lattice,
                         Lattice target)

minus

private static <E> java.util.Set<E> minus(java.util.Collection<E> c,
                                          java.util.Collection<E> c2)

frame

private LatticeSuggester.Frame frame(LatticeSuggester.Query q,
                                     RelNode r)