- All Superinterfaces:
- Enclosing class:
public static interface BuiltInMetadata.NonCumulativeCost extends Metadata
Metadata about the cost of evaluating a relational expression, not including its inputs.
Nested Class SummaryModifier and TypeInterfaceDescription
static interfaceHandler API.
getNonCumulativeCostRelOptCost getNonCumulativeCost()Estimates the cost of executing a relational expression, not counting the cost of its inputs. (However, the non-cumulative cost is still usually dependent on the row counts of the inputs.)
The default implementation for this query asks the rel itself via
RelNode.computeSelfCost(RelOptPlanner, RelMetadataQuery), but metadata providers can override this with their own cost models.
- estimated cost, or null if no reliable estimate can be determined