org.apache.calcite.rel.rules

Class ReduceExpressionsRule

java.lang.Object

org.apache.calcite.plan.RelOptRule

org.apache.calcite.rel.rules.ReduceExpressionsRule

public abstract class ReduceExpressionsRule
extends RelOptRule

Collection of planner rules that apply various simplifying transformations on RexNode trees. Currently, there are two transformations:

• Constant reduction, which evaluates constant subtrees, replacing them with a corresponding RexLiteral
• Removal of redundant casts, which occurs when the argument into the cast is the same as the type of the resulting cast expression

Field Summary

Fields

Modifier and Type	Field and Description
static ReduceExpressionsRule	CALC_INSTANCE
static Pattern	EXCLUSION_PATTERN Regular expression that matches the description of all instances of this rule and ValuesReduceRule also.
static ReduceExpressionsRule	FILTER_INSTANCE Singleton rule that reduces constants inside a LogicalFilter.
static ReduceExpressionsRule	JOIN_INSTANCE
static ReduceExpressionsRule	PROJECT_INSTANCE

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

description, operands

Method Summary

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

any, convert, convert, convertList, equals, equals, getOperand, getOperands, getOutConvention, getOutTrait, hashCode, matches, none, onMatch, 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

EXCLUSION_PATTERN

public static final Pattern EXCLUSION_PATTERN

Regular expression that matches the description of all instances of this rule and ValuesReduceRule also. Use it to prevent the planner from invoking these rules.

FILTER_INSTANCE

public static final ReduceExpressionsRule FILTER_INSTANCE

Singleton rule that reduces constants inside a LogicalFilter. If the condition is a constant, the filter is removed (if TRUE) or replaced with an empty Values (if FALSE or NULL).

PROJECT_INSTANCE

public static final ReduceExpressionsRule PROJECT_INSTANCE

JOIN_INSTANCE

public static final ReduceExpressionsRule JOIN_INSTANCE

CALC_INSTANCE

public static final ReduceExpressionsRule CALC_INSTANCE