org.apache.hadoop.hive.ql.optimizer.calcite.rules

Class HiveExpandDistinctAggregatesRule

java.lang.Object

org.apache.calcite.plan.RelOptRule

org.apache.hadoop.hive.ql.optimizer.calcite.rules.HiveExpandDistinctAggregatesRule

public final class HiveExpandDistinctAggregatesRule
extends org.apache.calcite.plan.RelOptRule

Planner rule that expands distinct aggregates (such as COUNT(DISTINCT x)) from a Aggregate.

How this is done depends upon the arguments to the function. If all functions have the same argument (e.g. COUNT(DISTINCT x), SUM(DISTINCT x) both have the argument x) then one extra Aggregate is sufficient.

If there are multiple arguments (e.g. COUNT(DISTINCT x), COUNT(DISTINCT y)) the rule creates separate Aggregates and combines using a Join.

Field Summary

Fields

Modifier and Type	Field and Description
static HiveExpandDistinctAggregatesRule	INSTANCE The default instance of the rule; operates only on logical expressions.

Fields inherited from class org.apache.calcite.plan.RelOptRule

description, operands

Constructor Summary

Constructors

Constructor and Description
HiveExpandDistinctAggregatesRule(Class<? extends org.apache.calcite.rel.core.Aggregate> clazz, org.apache.calcite.rel.core.RelFactories.ProjectFactory projectFactory)

Method Summary

Methods

Modifier and Type	Method and Description
void	onMatch(org.apache.calcite.plan.RelOptRuleCall call)

Methods inherited from class org.apache.calcite.plan.RelOptRule

any, convert, convert, convertList, equals, equals, getOperand, getOperands, getOutConvention, getOutTrait, hashCode, matches, none, operand, operand, operand, operand, operand, some, toString, unordered

Methods inherited from class java.lang.Object

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

Field Detail

INSTANCE

public static final HiveExpandDistinctAggregatesRule INSTANCE

The default instance of the rule; operates only on logical expressions.

Constructor Detail

HiveExpandDistinctAggregatesRule

public HiveExpandDistinctAggregatesRule(Class<? extends org.apache.calcite.rel.core.Aggregate> clazz,
                                org.apache.calcite.rel.core.RelFactories.ProjectFactory projectFactory)

Method Detail

onMatch

public void onMatch(org.apache.calcite.plan.RelOptRuleCall call)

Specified by:

onMatch in class org.apache.calcite.plan.RelOptRule