org.apache.calcite.rel.rules

Class JoinPushExpressionsRule

java.lang.Object

org.apache.calcite.plan.RelOptRule

org.apache.calcite.rel.rules.JoinPushExpressionsRule

public class JoinPushExpressionsRule
extends RelOptRule

Planner rule that pushes down expressions in "equal" join condition.

For example, given "emp JOIN dept ON emp.deptno + 1 = dept.deptno", adds a project above "emp" that computes the expression "emp.deptno + 1". The resulting join condition is a simple combination of AND, equals, and input fields, plus the remaining non-equal conditions.

Field Summary

Fields

Modifier and Type	Field and Description
static JoinPushExpressionsRule	INSTANCE

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

description, operands, relBuilderFactory

Constructor Summary

Constructors

Constructor and Description
JoinPushExpressionsRule(Class<? extends Join> clazz, RelBuilderFactory relBuilderFactory) Creates a JoinPushExpressionsRule.
JoinPushExpressionsRule(Class<? extends Join> clazz, RelFactories.ProjectFactory projectFactory) Deprecated.

Method Summary

Modifier and Type	Method and Description
void	onMatch(RelOptRuleCall call) Receives notification about a rule match.

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

any, convert, convert, convertList, convertOperand, 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 JoinPushExpressionsRule INSTANCE

Constructor Detail

JoinPushExpressionsRule

public JoinPushExpressionsRule(Class<? extends Join> clazz,
                               RelBuilderFactory relBuilderFactory)

Creates a JoinPushExpressionsRule.

JoinPushExpressionsRule

@Deprecated
public JoinPushExpressionsRule(Class<? extends Join> clazz,
                                           RelFactories.ProjectFactory projectFactory)

Deprecated.

Method Detail

onMatch

public void onMatch(RelOptRuleCall call)

Description copied from class: RelOptRule

Receives notification about a rule match. At the time that this method is called, call.rels holds the set of relational expressions which match the operands to the rule; call.rels[0] is the root expression.

Typically a rule would check that the nodes are valid matches, creates a new expression, then calls back RelOptRuleCall.transformTo(org.apache.calcite.rel.RelNode, java.util.Map<org.apache.calcite.rel.RelNode, org.apache.calcite.rel.RelNode>) to register the expression.

Specified by:

onMatch in class RelOptRule

Parameters:

call - Rule call

See Also:

RelOptRule.matches(RelOptRuleCall)