BuiltInMetadata.Distribution (Apache Calcite API)

All Superinterfaces:

Metadata

All Known Subinterfaces:

BuiltInMetadata.All

Enclosing class:

BuiltInMetadata
```
public static interface BuiltInMetadata.Distribution
extends Metadata
```
Metadata about how a relational expression is distributed.
If you are an operator consuming a relational expression, which subset of the rows are you seeing? You might be seeing all of them (BROADCAST or SINGLETON), only those whose key column values have a particular hash code (HASH) or only those whose column values have particular values or ranges of values (RANGE).
When a relational expression is partitioned, it is often partitioned among nodes, but it may be partitioned among threads running on the same node.

- Nested Class Summary
  
  Nested Classes
  Modifier and Type Interface Description
  
  static interface BuiltInMetadata.Distribution.Handler
  Handler API.
- Field Summary
  
  Fields
  Modifier and Type Field Description
  
  static MetadataDef<BuiltInMetadata.Distribution> DEF
- Method Summary
  
  All Methods Instance Methods Abstract Methods
  Modifier and Type Method Description
  
  RelDistribution distribution()
  Determines how the rows are distributed.
  - Methods inherited from interface org.apache.calcite.rel.metadata.Metadata
    rel

Field Detail

DEF

static final MetadataDef<BuiltInMetadata.Distribution> DEF

Method Detail
- distribution
```
RelDistribution distribution()
```
  Determines how the rows are distributed.