com.apple.foundationdb.record.query.plan.temp.properties

Class UnmatchedFieldsProperty

java.lang.Object

com.apple.foundationdb.record.query.plan.temp.properties.UnmatchedFieldsProperty

All Implemented Interfaces:

PlannerProperty<Integer>

@API(value=EXPERIMENTAL)
public class UnmatchedFieldsProperty
extends Object
implements PlannerProperty<Integer>

A property for counting the total number of KeyExpression columns (i.e., field-like KeyExpressions such as FieldKeyExpression and RecordTypeKeyExpression) that are not matched with at least one Comparisons.Comparison in a planner expression tree. This is computed over all KeyExpressions in various IndexEntrySourceScanExpressions.

For example, suppose that a planner expression scans two indexes:

• concat(field1, field2), with a comparison field1 = 'foo'
• concat(field1, field3, field4), with a comparison field1 = 'foo', field3 < 5

The UnmatchedFieldsProperty on such a planner expression is 2.

Constructor Summary

Constructors

Constructor and Description
UnmatchedFieldsProperty(PlanContext context)

Method Summary

Modifier and Type	Method and Description
static int	evaluate(PlanContext context, PlannerExpression expression)
Integer	evaluateAtExpression(PlannerExpression expression, List<Integer> childResults) Evaluate the property at the given expression, using the results of evaluating the property at its children.
Integer	evaluateAtRef(ExpressionRef<? extends PlannerExpression> ref, List<Integer> memberResults) Evaluate the property at the given reference, using the results of evaluating the property at its members.
boolean	shouldVisit(ExpressionRef<? extends PlannerExpression> ref) Return whether the property should visit the subtree rooted at the given expression.
boolean	shouldVisit(PlannerExpression expression) Return whether the property should visit the subtree rooted at the given expression.

Methods inherited from class java.lang.Object

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

Constructor Detail

UnmatchedFieldsProperty

public UnmatchedFieldsProperty(@Nonnull
                               PlanContext context)

Method Detail

shouldVisit

public boolean shouldVisit(@Nonnull
                           PlannerExpression expression)

Description copied from interface: PlannerProperty

Return whether the property should visit the subtree rooted at the given expression. Called on nodes in the expression tree in visit pre-order of the depth-first traversal of the tree. That is, as each node is visited for the first time, shouldVisit() is called on that node. If shouldVisit() returns false, then PlannerProperty.evaluateAtExpression(PlannerExpression, List) will not be called on the given expression.

Specified by:

shouldVisit in interface PlannerProperty<Integer>

Parameters:

expression - the planner expression to visit

Returns:

true if the children of expression should be visited and false if they should not be visited

shouldVisit

public boolean shouldVisit(@Nonnull
                           ExpressionRef<? extends PlannerExpression> ref)

Description copied from interface: PlannerProperty

Return whether the property should visit the subtree rooted at the given expression. Called on nodes in the expression tree in visit pre-order of the depth-first traversal of the tree. That is, as each node is visited for the first time, shouldVisit() is called on that node. If shouldVisit() returns false, then PlannerProperty.evaluateAtRef(ExpressionRef, List) will not be called on the given expression.

Specified by:

shouldVisit in interface PlannerProperty<Integer>

Parameters:

ref - the expression reference to visit

Returns:

true if the members of ref should be visited and false if they should not be visited

evaluateAtExpression

@Nonnull
public Integer evaluateAtExpression(@Nonnull
                                             PlannerExpression expression,
                                             @Nonnull
                                             List<Integer> childResults)

Description copied from interface: PlannerProperty

Evaluate the property at the given expression, using the results of evaluating the property at its children. Called on nodes in the expression tree in visit post-order of the depth-first traversal of the tree. That is, as each node is visited for the last time (after all of its children have been visited, if applicable), evaluateAtExpression() is called on that node.

Specified by:

evaluateAtExpression in interface PlannerProperty<Integer>

Parameters:

expression - the cursor to visit

childResults - the results of the property evaluated at the children of expression

Returns:

the value of property at the given expression

evaluateAtRef

@Nonnull
public Integer evaluateAtRef(@Nonnull
                                      ExpressionRef<? extends PlannerExpression> ref,
                                      @Nonnull
                                      List<Integer> memberResults)

Description copied from interface: PlannerProperty

Evaluate the property at the given reference, using the results of evaluating the property at its members. Called on nodes in the expression tree in visit post-order of the depth-first traversal of the tree. That is, as each node is visited for the last time (after all of its children have been visited, if applicable), evaluateAtRef() is called on that node.

Specified by:

evaluateAtRef in interface PlannerProperty<Integer>

Parameters:

ref - the expression reference to visit

memberResults - the results of the property evaluated at the members of ref

Returns:

the value of property at the given reference

evaluate

public static int evaluate(@Nonnull
                           PlanContext context,
                           @Nonnull
                           PlannerExpression expression)