@Immutable public class AddAccessNodes extends Object implements OptimizerRule
optimizer rule
that inserts an ACCESS above each SOURCE leaf node in a query plan. This rule is often
the first rule to run against a canonical plan
(see
RuleBasedOptimizer.populateRuleStack(LinkedList, PlanHints)
.
Before:
... | SOURCEAfter:
... | ACCESS | SOURCE
Modifier and Type | Field and Description |
---|---|
static AddAccessNodes |
INSTANCE |
Constructor and Description |
---|
AddAccessNodes() |
Modifier and Type | Method and Description |
---|---|
PlanNode |
execute(QueryContext context,
PlanNode plan,
LinkedList<OptimizerRule> ruleStack)
Optimize the supplied plan using the supplied context, hints, and yet-to-be-run rules.
|
String |
toString() |
public static final AddAccessNodes INSTANCE
public PlanNode execute(QueryContext context, PlanNode plan, LinkedList<OptimizerRule> ruleStack)
OptimizerRule
execute
in interface OptimizerRule
context
- the context in which the query is being optimized; never nullplan
- the plan to be optimized; never nullruleStack
- the stack of rules that will be run after this rule; never nullCopyright © 2008–2016 JBoss, a division of Red Hat. All rights reserved.