Package org.apache.calcite.rel.metadata

Class RelColumnOrigin

java.lang.Object

org.apache.calcite.rel.metadata.RelColumnOrigin

public class RelColumnOrigin
extends Object

RelColumnOrigin is a data structure describing one of the origins of an output column produced by a relational expression.

Constructor Summary

Constructors

Constructor	Description
RelColumnOrigin(RelOptTable originTable, int iOriginColumn, boolean isDerived)

Method Summary

Modifier and Type	Method	Description
boolean	equals(@Nullable Object obj)
int	getOriginColumnOrdinal()	Returns the 0-based index of column in origin table; whether this ordinal is flattened or unflattened depends on whether UDT flattening has already been performed on the relational expression which produced this description.
RelOptTable	getOriginTable()	Returns table of origin.
int	hashCode()
boolean	isDerived()	Consider the query select a+b as c, d as e from t.

Methods inherited from class java.lang.Object

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

Constructor Details

RelColumnOrigin

public RelColumnOrigin(RelOptTable originTable,
 int iOriginColumn,
 boolean isDerived)

Method Details

getOriginTable

public RelOptTable getOriginTable()

Returns table of origin.

getOriginColumnOrdinal

public int getOriginColumnOrdinal()

Returns the 0-based index of column in origin table; whether this ordinal is flattened or unflattened depends on whether UDT flattening has already been performed on the relational expression which produced this description.

isDerived

public boolean isDerived()

Consider the query select a+b as c, d as e from t. The output column c has two origins (a and b), both of them derived. The output column e has one origin (d), which is not derived.

Returns:

false if value taken directly from column in origin table; true otherwise

equals

public boolean equals(@Nullable Object obj)

Overrides:

equals in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object