public CostEstimate estimateCostSpatial(SingleIndexScan index) {
PlanCostEstimator estimator = newEstimator();
Set<TableSource> requiredTables = requiredColumns.getTables();
estimator.spatialIndex(index);
if (!index.isCovering()) {
estimator.flatten(tables, index.getLeafMostTable(), requiredTables);
}