Add cached device number info for last query

Author: shuwenwei

iotdb-core/datanode/src/main/java/org/apache/iotdb/db/queryengine/execution/operator/source/relational/LastQueryAggTableScanOperator.java

@@ -26,6 +26,7 @@
 import org.apache.iotdb.db.queryengine.execution.operator.source.relational.aggregation.LastByDescAccumulator;
 import org.apache.iotdb.db.queryengine.execution.operator.source.relational.aggregation.LastDescAccumulator;
 import org.apache.iotdb.db.queryengine.execution.operator.source.relational.aggregation.TableAggregator;
+import org.apache.iotdb.db.queryengine.plan.planner.plan.node.PlanGraphPrinter;
 import org.apache.iotdb.db.queryengine.plan.relational.metadata.ColumnSchema;
 import org.apache.iotdb.db.queryengine.plan.relational.metadata.DeviceEntry;
 import org.apache.iotdb.db.queryengine.plan.relational.metadata.QualifiedObjectName;
@@ -96,6 +97,8 @@ public LastQueryAggTableScanOperator(
     this.hitCachedResults = hitCachedResults;
     this.dbName = qualifiedObjectName.getDatabaseName();
 
+    this.operatorContext.recordSpecifiedInfo(
+        PlanGraphPrinter.CACHED_DEVICE_NUMBER, Integer.toString(cachedDeviceEntries.size()));
     for (int i = 0; i < parameter.tableAggregators.size(); i++) {
       if (parameter.tableAggregators.get(i).getAccumulator() instanceof LastAccumulator) {
         lastTimeAggregationIdx = i;

iotdb-core/datanode/src/main/java/org/apache/iotdb/db/queryengine/plan/planner/plan/node/PlanGraphPrinter.java

@@ -119,6 +119,7 @@ public class PlanGraphPrinter extends PlanVisitor<List<String>, PlanGraphPrinter
 
   private static final String REGION_NOT_ASSIGNED = "Not Assigned";
   public static final String DEVICE_NUMBER = "DeviceNumber";
+  public static final String CACHED_DEVICE_NUMBER = "CachedDeviceNumber";
   public static final String CURRENT_USED_MEMORY = "CurrentUsedMemory";
   public static final String MAX_USED_MEMORY = "MaxUsedMemory";
   public static final String MAX_RESERVED_MEMORY = "MaxReservedMemory";