Statistic (Apache Calcite API)

```
public interface Statistic
```
Statistics about a Table.
Each of the methods may return null meaning "not known".

See Also:

Statistics

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method	Description
`java.util.List<RelCollation>`	`getCollations()`	Returns the collections of columns on which this table is sorted.
`RelDistribution`	`getDistribution()`	Returns the distribution of the data in this table.
`java.util.List<RelReferentialConstraint>`	`getReferentialConstraints()`	Returns the collection of referential constraints (foreign-keys) for this table.
`java.lang.Double`	`getRowCount()`	Returns the approximate number of rows in the table.
`boolean`	`isKey(ImmutableBitSet columns)`	Returns whether the given set of columns is a unique key, or a superset of a unique key, of the table.

- Method Detail
  - getRowCount
```
java.lang.Double getRowCount()
```
    Returns the approximate number of rows in the table.
  - isKey
```
boolean isKey(ImmutableBitSet columns)
```
    Returns whether the given set of columns is a unique key, or a superset of a unique key, of the table.
  - getReferentialConstraints
```
java.util.List<RelReferentialConstraint> getReferentialConstraints()
```
    Returns the collection of referential constraints (foreign-keys) for this table.
  - getCollations
```
java.util.List<RelCollation> getCollations()
```
    Returns the collections of columns on which this table is sorted.
  - getDistribution
```
RelDistribution getDistribution()
```
    Returns the distribution of the data in this table.