[iotdb] branch rel/0.11 updated: optimize max_time with value filter (#1979)

[qi...@apache.org]

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qiaojialin pushed a commit to branch rel/0.11
in repository https://gitbox.apache.org/repos/asf/iotdb.git


The following commit(s) were added to refs/heads/rel/0.11 by this push:
     new 8ff002a  optimize max_time with value filter (#1979)
8ff002a is described below

commit 8ff002a5f81a2930d4cc911c5b486ec1db28d466
Author: Xiangwei Wei <34...@users.noreply.github.com>
AuthorDate: Sat Nov 7 13:52:15 2020 +0800

    optimize max_time with value filter (#1979)
    
    (cherry picked from commit 8df4d57ffd3d1fdf2b55724a64a5553e48d092c2)
---
 .../java/org/apache/iotdb/db/conf/IoTDBConstant.java     |  1 +
 .../iotdb/db/query/executor/AggregationExecutor.java     | 16 ++++++++++++++--
 2 files changed, 15 insertions(+), 2 deletions(-)

diff --git a/server/src/main/java/org/apache/iotdb/db/conf/IoTDBConstant.java b/server/src/main/java/org/apache/iotdb/db/conf/IoTDBConstant.java
index 2ea59a2..2b62db9 100644
--- a/server/src/main/java/org/apache/iotdb/db/conf/IoTDBConstant.java
+++ b/server/src/main/java/org/apache/iotdb/db/conf/IoTDBConstant.java
@@ -54,6 +54,7 @@ public class IoTDBConstant {
   public static final String PROFILE_SUFFIX = ".profile";
   public static final String MAX_TIME = "max_time";
   public static final String MIN_TIME = "min_time";
+  public static final String LAST_VALUE = "last_value";
   public static final int MIN_SUPPORTED_JDK_VERSION = 8;
 
   // show info
diff --git a/server/src/main/java/org/apache/iotdb/db/query/executor/AggregationExecutor.java b/server/src/main/java/org/apache/iotdb/db/query/executor/AggregationExecutor.java
index 17e953e..568eb7d 100644
--- a/server/src/main/java/org/apache/iotdb/db/query/executor/AggregationExecutor.java
+++ b/server/src/main/java/org/apache/iotdb/db/query/executor/AggregationExecutor.java
@@ -26,6 +26,7 @@ import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
+import org.apache.iotdb.db.conf.IoTDBConstant;
 import org.apache.iotdb.db.conf.IoTDBDescriptor;
 import org.apache.iotdb.db.engine.querycontext.QueryDataSource;
 import org.apache.iotdb.db.exception.StorageEngineException;
@@ -62,7 +63,7 @@ public class AggregationExecutor {
   protected List<TSDataType> dataTypes;
   protected List<String> aggregations;
   protected IExpression expression;
-  protected final boolean ascending;
+  protected boolean ascending;
 
   /**
    * aggregation batch calculation size.
@@ -283,7 +284,18 @@ public class AggregationExecutor {
    */
   public QueryDataSet executeWithValueFilter(QueryContext context, RawDataQueryPlan queryPlan)
       throws StorageEngineException, IOException, QueryProcessException {
-
+    int index = 0;
+    for (; index < aggregations.size(); index++) {
+      String aggregationFunc = aggregations.get(index);
+      if (!aggregationFunc.equals(IoTDBConstant.MAX_TIME) && !aggregationFunc
+          .equals(IoTDBConstant.LAST_VALUE)) {
+        break;
+      }
+    }
+    if (index >= aggregations.size()) {
+      queryPlan.setAscending(false);
+      this.ascending = false;
+    }
     TimeGenerator timestampGenerator = getTimeGenerator(context, queryPlan);
     List<IReaderByTimestamp> readersOfSelectedSeries = new ArrayList<>();
     for (int i = 0; i < selectedSeries.size(); i++) {