Package org.apache.calcite.materialize

Management of materialized query results.

An actor (MaterializationActor) maintains the state of all materializations in the system and is wrapped in a service (MaterializationService) for access from other parts of the system.

Optimizer rules allow Calcite to rewrite queries using materializations, if they are valid (that is, contain the same result as executing their defining query) and lower cost.

In future, the actor may manage the process of updating materializations, instantiating materializations from the intermediate results of queries, and recognize what materializations would be useful based on actual query load.

Interface Summary

Interface	Description
LatticeStatisticProvider	Estimates row counts for a lattice and its attributes.
LatticeStatisticProvider.Factory	Creates a LatticeStatisticProvider for a given Lattice.
MaterializationService.TableFactory	Creates tables that represent a materialized view.
SqlStatisticProvider	Estimates row counts for tables and columns.

Class Summary

Class	Description
CachingLatticeStatisticProvider	Implementation of LatticeStatisticProvider that caches single-column statistics and computes multi-column statistics from these.
DelegatingLatticeStatisticProvider	Implementation of LatticeStatisticProvider that delegates to an underlying provider.
Lattice	Structure that allows materialized views based upon a star schema to be recognized and recommended.
Lattice.BaseColumn	Column in a lattice.
Lattice.Builder	Lattice builder.
Lattice.Builder.Fixer	Work space for fixing up a tree of mutable nodes.
Lattice.Column	Column in a lattice.
Lattice.DerivedColumn	Column in a lattice that is based upon a SQL expression.
Lattice.Edge	Edge in the temporary graph.
Lattice.Measure	A measure within a Lattice.
Lattice.SqlWriter	The information necessary to convert a column to SQL.
Lattice.Tile	Materialized aggregate within a lattice.
Lattice.TileBuilder	Tile builder.
Lattice.Vertex	Vertex in the temporary graph.
LatticeChildNode	Non-root node in a Lattice.
LatticeNode	Source relation of a lattice.
LatticeRootNode	Root node in a Lattice.
Lattices	Utilities for Lattice, LatticeStatisticProvider.
LatticeSpace	Space within which lattices exist.
LatticeSuggester	Algorithm that suggests a set of lattices.
LatticeSuggester.BaseColRef	Reference to a base column.
LatticeSuggester.ColRef	Column reference.
LatticeSuggester.DerivedColRef	Reference to a derived column (that is, an expression).
LatticeSuggester.Frame	Information about the parent of fields from a relational expression.
LatticeSuggester.Hop	A hop is a join condition.
LatticeSuggester.MutableMeasure	An aggregate call.
LatticeSuggester.Query	Holds state for a particular query graph.
LatticeSuggester.StepRef	Use of a step within a query.
LatticeSuggester.StepRef.Factory	Creates LatticeSuggester.StepRef instances.
LatticeSuggester.TableRef	Use of a table within a query.
LatticeTable	Table registered in the graph.
MaterializationActor	Actor that manages the state of materializations in the system.
MaterializationActor.Materialization	A query materialized in a table, so that reading from the table gives the same results as executing the query.
MaterializationActor.QueryKey	A materialization can be re-used if it is the same SQL, on the same schema, with the same path for resolving functions.
MaterializationKey	Unique identifier for a materialization.
MaterializationService	Manages the collection of materialized tables known to the system, and the process by which they become valid and invalid.
MaterializationService.DefaultTableFactory	Default implementation of MaterializationService.TableFactory.
MutableNode	Mutable version of LatticeNode, used while a graph is being built.
Path	A sequence of Steps from a root node (fact table) to another node (dimension table), possibly via intermediate dimension tables.
ProfilerLatticeStatisticProvider	Implementation of LatticeStatisticProvider that uses a Profiler.
SqlLatticeStatisticProvider	Implementation of LatticeStatisticProvider that gets statistics by executing "SELECT COUNT(DISTINCT ...) ..." SQL queries.
Step	Edge in the join graph.
Step.Factory	Creates Step instances.
TileKey	Definition of a particular combination of dimensions and measures of a lattice that is the basis of a materialization.
TileSuggester	Algorithm that suggests a set of initial tiles (materialized aggregate views) for a given lattice.
TileSuggester.AttributeImpl	Implementation of Attribute based on a Lattice.Column.
TileSuggester.SchemaImpl	Implementation of Schema based on a Lattice.
TileSuggester.StatisticsProviderImpl	Implementation of StatisticsProvider that asks the lattice.
TileSuggester.TableImpl	Implementation of Table based on a Lattice.

Enum Summary

Enum	Description
MapSqlStatisticProvider	Implementation of SqlStatisticProvider that looks up values in a table.