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 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

package org.apache.iotdb.db.queryengine.plan.relational.analyzer;

import org.apache.iotdb.db.queryengine.plan.planner.plan.LogicalQueryPlan;
import org.apache.iotdb.db.queryengine.plan.relational.planner.PlanTester;
import org.apache.iotdb.db.queryengine.plan.relational.sql.ast.ArithmeticBinaryExpression;
import org.apache.iotdb.db.queryengine.plan.relational.sql.ast.ComparisonExpression;
import org.apache.iotdb.db.queryengine.plan.relational.sql.ast.FunctionCall;
import org.apache.iotdb.db.queryengine.plan.relational.sql.ast.LongLiteral;
import org.apache.iotdb.db.queryengine.plan.relational.sql.ast.QualifiedName;
import org.apache.iotdb.db.queryengine.plan.relational.sql.ast.SymbolReference;

import com.google.common.collect.ImmutableList;
import com.google.common.collect.ImmutableMap;
import com.google.common.collect.ImmutableSet;
import org.junit.Test;

import java.util.Optional;

import static org.apache.iotdb.db.queryengine.plan.relational.planner.assertions.PlanAssert.assertPlan;
import static org.apache.iotdb.db.queryengine.plan.relational.planner.assertions.PlanMatchPattern.aggregation;
import static org.apache.iotdb.db.queryengine.plan.relational.planner.assertions.PlanMatchPattern.aggregationFunction;
import static org.apache.iotdb.db.queryengine.plan.relational.planner.assertions.PlanMatchPattern.aggregationTableScan;
import static org.apache.iotdb.db.queryengine.plan.relational.planner.assertions.PlanMatchPattern.collect;
import static org.apache.iotdb.db.queryengine.plan.relational.planner.assertions.PlanMatchPattern.exchange;
import static org.apache.iotdb.db.queryengine.plan.relational.planner.assertions.PlanMatchPattern.expression;
import static org.apache.iotdb.db.queryengine.plan.relational.planner.assertions.PlanMatchPattern.filter;
import static org.apache.iotdb.db.queryengine.plan.relational.planner.assertions.PlanMatchPattern.mergeSort;
import static org.apache.iotdb.db.queryengine.plan.relational.planner.assertions.PlanMatchPattern.output;
import static org.apache.iotdb.db.queryengine.plan.relational.planner.assertions.PlanMatchPattern.project;
import static org.apache.iotdb.db.queryengine.plan.relational.planner.assertions.PlanMatchPattern.singleGroupingSet;
import static org.apache.iotdb.db.queryengine.plan.relational.planner.assertions.PlanMatchPattern.tableScan;
import static org.apache.iotdb.db.queryengine.plan.relational.planner.node.AggregationNode.Step.FINAL;
import static org.apache.iotdb.db.queryengine.plan.relational.planner.node.AggregationNode.Step.INTERMEDIATE;
import static org.apache.iotdb.db.queryengine.plan.relational.planner.node.AggregationNode.Step.PARTIAL;
import static org.apache.iotdb.db.queryengine.plan.relational.planner.node.AggregationNode.Step.SINGLE;
import static org.apache.iotdb.db.queryengine.plan.relational.sql.ast.ArithmeticBinaryExpression.Operator.ADD;
import static org.apache.iotdb.db.queryengine.plan.relational.sql.ast.ArithmeticBinaryExpression.Operator.MULTIPLY;
import static org.apache.iotdb.db.queryengine.plan.relational.sql.ast.ComparisonExpression.Operator.LESS_THAN;

// This test covers the remaining DistributionPlan cases that TSBSTest doesn't cover
public class AggregationTest {
  @Test
  public void noPushDownTest() {
    PlanTester planTester = new PlanTester();

    // Measurement column appears in groupingKeys
    // Output - Project - Aggregation - TableScan
    LogicalQueryPlan logicalQueryPlan =
        planTester.createPlan("SELECT count(s2) FROM table1 group by s1");
    assertPlan(
        logicalQueryPlan,
        output(
            project(
                aggregation(
                    singleGroupingSet("s1"),
                    ImmutableMap.of(
                        Optional.empty(), aggregationFunction("count", ImmutableList.of("s2"))),
                    ImmutableList.of(), // UnStreamable
                    Optional.empty(),
                    SINGLE,
                    tableScan(
                        "testdb.table1",
                        ImmutableList.of("s1", "s2"),
                        ImmutableSet.of("s1", "s2"))))));

    //                               - Exchange
    // Output - Project - Agg(FINAL) - Collect - Agg(PARTIAL) - TableScan
    //                               - Exchange
    assertPlan(
        planTester.getFragmentPlan(0),
        output(
            project(
                aggregation(
                    singleGroupingSet("s1"),
                    ImmutableMap.of(
                        Optional.empty(),
                        aggregationFunction("count", ImmutableList.of("count_0"))),
                    ImmutableList.of(), // UnStreamable
                    Optional.empty(),
                    FINAL,
                    collect(exchange(), exchange(), exchange())))));
    // Agg(PARTIAL) - TableScan
    for (int i = 1; i <= 3; i++) {
      assertPlan(
          planTester.getFragmentPlan(i),
          aggregation(
              singleGroupingSet("s1"),
              ImmutableMap.of(
                  Optional.of("count_0"), aggregationFunction("count", ImmutableList.of("s2"))),
              ImmutableList.of(), // UnStreamable
              Optional.empty(),
              PARTIAL,
              tableScan(
                  "testdb.table1", ImmutableList.of("s1", "s2"), ImmutableSet.of("s1", "s2"))));
    }

    // Output - Project - Aggregation - TableScan
    assertPlan(
        planTester.createPlan("SELECT count(s2) FROM table1 group by s1, tag1, tag2, tag3, time"),
        output(
            project(
                aggregation(
                    singleGroupingSet("s1", "tag1", "tag2", "tag3", "time"),
                    ImmutableMap.of(
                        Optional.empty(), aggregationFunction("count", ImmutableList.of("s2"))),
                    ImmutableList.of("tag1", "tag2", "tag3"), // Streamable
                    Optional.empty(),
                    SINGLE,
                    tableScan(
                        "testdb.table1",
                        ImmutableList.of("time", "tag1", "tag2", "tag3", "s1", "s2"),
                        ImmutableSet.of("time", "tag1", "tag2", "tag3", "s1", "s2"))))));

    //                               - Exchange
    // Output - Project - Agg(FINAL) - MergeSort - Agg(PARTIAL) - TableScan
    //                               - Exchange
    assertPlan(
        planTester.getFragmentPlan(0),
        output(
            project(
                aggregation(
                    singleGroupingSet("s1", "tag1", "tag2", "tag3", "time"),
                    ImmutableMap.of(
                        Optional.empty(),
                        aggregationFunction("count", ImmutableList.of("count_0"))),
                    ImmutableList.of("tag1", "tag2", "tag3"), // Streamable
                    Optional.empty(),
                    FINAL,
                    mergeSort(exchange(), exchange(), exchange())))));
    for (int i = 1; i <= 3; i++) {
      assertPlan(
          planTester.getFragmentPlan(i),
          aggregation(
              singleGroupingSet("s1", "tag1", "tag2", "tag3", "time"),
              ImmutableMap.of(
                  Optional.of("count_0"), aggregationFunction("count", ImmutableList.of("s2"))),
              ImmutableList.of("tag1", "tag2", "tag3"), // Streamable
              Optional.empty(),
              PARTIAL,
              tableScan(
                  "testdb.table1",
                  ImmutableList.of("time", "tag1", "tag2", "tag3", "s1", "s2"),
                  ImmutableSet.of("time", "tag1", "tag2", "tag3", "s1", "s2"))));
    }
    // TODO Add more tests about streamable when develop subquery, especially when there is SortNode

    // Expr appears in groupingKeys, and it is not date_bin(time)
    // Output - Project - Aggregation - Project - TableScan
    logicalQueryPlan =
        planTester.createPlan("SELECT count(s2) FROM table1 group by substring(tag1,1)");
    assertPlan(
        logicalQueryPlan,
        output(
            project(
                aggregation(
                    singleGroupingSet("substring"),
                    ImmutableMap.of(
                        Optional.empty(), aggregationFunction("count", ImmutableList.of("s2"))),
                    ImmutableList.of(), // UnStreamable
                    Optional.empty(),
                    SINGLE,
                    project(
                        ImmutableMap.of(
                            "substring",
                            expression(
                                new FunctionCall(
                                    QualifiedName.of("substring"),
                                    ImmutableList.of(
                                        new SymbolReference("tag1"), new LongLiteral("1"))))),
                        tableScan(
                            "testdb.table1",
                            ImmutableList.of("tag1", "s2"),
                            ImmutableSet.of("tag1", "s2")))))));

    // Value filter exists and cannot be push-down
    // Output - Project - Aggregation - Project - TableScan (The value filter has been push-down)
    logicalQueryPlan =
        planTester.createPlan("SELECT count(s2) FROM table1 where s1*s2 < 1 group by tag1");
    assertPlan(
        logicalQueryPlan,
        output(
            project(
                aggregation(
                    singleGroupingSet("tag1"),
                    ImmutableMap.of(
                        Optional.empty(), aggregationFunction("count", ImmutableList.of("s2"))),
                    ImmutableList.of("tag1"), // Streamable
                    Optional.empty(),
                    SINGLE,
                    project(
                        filter(
                            new ComparisonExpression(
                                LESS_THAN,
                                new ArithmeticBinaryExpression(
                                    MULTIPLY, new SymbolReference("s1"), new SymbolReference("s2")),
                                new LongLiteral("1")),
                            tableScan(
                                "testdb.table1",
                                ImmutableList.of("tag1", "s1", "s2"),
                                ImmutableSet.of("tag1", "s2", "s1"))))))));

    // Expr appears in arguments of AggFunction
    // Output - Project - Aggregation - Project - TableScan
    logicalQueryPlan = planTester.createPlan("SELECT count(s2+1) FROM table1 group by tag1");
    assertPlan(
        logicalQueryPlan,
        output(
            project(
                aggregation(
                    singleGroupingSet("tag1"),
                    ImmutableMap.of(
                        Optional.empty(), aggregationFunction("count", ImmutableList.of("expr_1"))),
                    ImmutableList.of("tag1"), // Streamable
                    Optional.empty(),
                    SINGLE,
                    project(
                        ImmutableMap.of(
                            "expr_1",
                            expression(
                                new ArithmeticBinaryExpression(
                                    ADD, new SymbolReference("s2"), new LongLiteral("1")))),
                        tableScan(
                            "testdb.table1",
                            ImmutableList.of("tag1", "s2"),
                            ImmutableSet.of("tag1", "s2")))))));

    // don't push down when time appears in group by
    logicalQueryPlan =
        planTester.createPlan(
            "SELECT count(s2) FROM table1 group by tag1, tag2, tag3, attr1, time");
    assertPlan(
        logicalQueryPlan,
        output(
            project(
                aggregation(
                    singleGroupingSet("tag1", "tag2", "tag3", "attr1", "time"),
                    ImmutableMap.of(
                        Optional.empty(), aggregationFunction("count", ImmutableList.of("s2"))),
                    ImmutableList.of("tag1", "tag2", "tag3", "attr1"), // Streamable
                    Optional.empty(),
                    SINGLE,
                    tableScan(
                        "testdb.table1",
                        ImmutableList.of("time", "tag1", "tag2", "tag3", "attr1", "s2"),
                        ImmutableSet.of("time", "tag1", "tag2", "tag3", "attr1", "s2"))))));
  }

  @Test
  public void partialPushDownTest() {
    PlanTester planTester = new PlanTester();

    // Only partial ID columns appear in GroupingKeys
    // Output - Project - Aggregation - AggTableScan
    LogicalQueryPlan logicalQueryPlan =
        planTester.createPlan("SELECT count(s2) FROM table1 group by tag1");
    assertPlan(
        logicalQueryPlan,
        output(
            project(
                aggregation(
                    singleGroupingSet("tag1"),
                    ImmutableMap.of(
                        Optional.empty(),
                        aggregationFunction("count", ImmutableList.of("count_0"))),
                    ImmutableList.of("tag1"), // Streamable
                    Optional.empty(),
                    FINAL,
                    aggregationTableScan(
                        singleGroupingSet("tag1"),
                        ImmutableList.of("tag1"), // Streamable
                        Optional.empty(),
                        PARTIAL,
                        "testdb.table1",
                        ImmutableList.of("tag1", "count_0"),
                        ImmutableSet.of("tag1", "s2"))))));

    // Only Attribute columns appear in GroupingKeys
    // Output - Project - Aggregation - AggTableScan
    logicalQueryPlan = planTester.createPlan("SELECT count(s2) FROM table1 group by attr1");
    assertPlan(
        logicalQueryPlan,
        output(
            project(
                aggregation(
                    singleGroupingSet("attr1"),
                    ImmutableMap.of(
                        Optional.empty(),
                        aggregationFunction("count", ImmutableList.of("count_0"))),
                    ImmutableList.of("attr1"), // Streamable
                    Optional.empty(),
                    FINAL,
                    aggregationTableScan(
                        singleGroupingSet("attr1"),
                        ImmutableList.of("attr1"), // Streamable
                        Optional.empty(),
                        PARTIAL,
                        "testdb.table1",
                        ImmutableList.of("attr1", "count_0"),
                        ImmutableSet.of("attr1", "s2"))))));

    // Only partial ID columns, Attribute columns, time or date_bin(time) appear in GroupingKeys
    // Output - Project - Aggregation - AggTableScan
    logicalQueryPlan =
        planTester.createPlan(
            "SELECT count(s2) FROM table1 group by attr1, tag1, date_bin(1h, time)");
    assertPlan(
        logicalQueryPlan,
        output(
            project(
                aggregation(
                    singleGroupingSet("attr1", "tag1", "date_bin$gid"),
                    ImmutableMap.of(
                        Optional.empty(),
                        aggregationFunction("count", ImmutableList.of("count_0"))),
                    ImmutableList.of("attr1", "tag1"), // Streamable
                    Optional.empty(),
                    FINAL,
                    aggregationTableScan(
                        singleGroupingSet("attr1", "tag1", "date_bin$gid"),
                        ImmutableList.of("attr1", "tag1"), // Streamable
                        Optional.empty(),
                        PARTIAL,
                        "testdb.table1",
                        ImmutableList.of("attr1", "tag1", "date_bin$gid", "count_0"),
                        ImmutableSet.of("attr1", "tag1", "time", "s2"))))));

    // GlobalAggregation with more than one DeviceEntry
    // Output - Aggregation - AggTableScan
    assertPlan(
        planTester.createPlan("SELECT count(s2) FROM table1"),
        output(
            aggregation(
                singleGroupingSet(),
                ImmutableMap.of(
                    Optional.empty(), aggregationFunction("count", ImmutableList.of("count_0"))),
                ImmutableList.of(),
                Optional.empty(),
                FINAL,
                aggregationTableScan(
                    singleGroupingSet(),
                    ImmutableList.of(), // UnStreamable
                    Optional.empty(),
                    PARTIAL,
                    "testdb.table1",
                    ImmutableList.of("count_0"),
                    ImmutableSet.of("s2")))));

    // Output - Aggregation(FINAL) - Collect - Aggregation(INTERMEDIATE) - AggTableScan
    assertPlan(
        planTester.getFragmentPlan(0),
        output(
            aggregation(
                singleGroupingSet(),
                ImmutableMap.of(
                    Optional.empty(), aggregationFunction("count", ImmutableList.of("count_1"))),
                ImmutableList.of(),
                Optional.empty(),
                FINAL,
                collect(exchange(), exchange(), exchange()))));

    // - Aggregation(INTERMEDIATE) - AggTableScan
    for (int i = 1; i <= 3; i++) {
      assertPlan(
          planTester.getFragmentPlan(i),
          aggregation(
              singleGroupingSet(),
              ImmutableMap.of(
                  Optional.of("count_1"),
                  aggregationFunction("count", ImmutableList.of("count_0"))),
              ImmutableList.of(),
              Optional.empty(),
              INTERMEDIATE,
              aggregationTableScan(
                  singleGroupingSet(),
                  ImmutableList.of(), // UnStreamable
                  Optional.empty(),
                  PARTIAL,
                  "testdb.table1",
                  ImmutableList.of("count_0"),
                  ImmutableSet.of("s2"))));
    }
  }

  @Test
  public void completePushDownTest() {
    PlanTester planTester = new PlanTester();

    // All ID columns appear in GroupingKeys
    // Output - Project - AggTableScan
    LogicalQueryPlan logicalQueryPlan =
        planTester.createPlan(
            "SELECT count(s2) FROM table1 where tag1!='shenzhen' group by tag1, tag2, tag3");
    assertPlan(
        logicalQueryPlan,
        output(
            project(
                aggregationTableScan(
                    singleGroupingSet("tag1", "tag2", "tag3"),
                    ImmutableList.of("tag1", "tag2", "tag3"), // Streamable
                    Optional.empty(),
                    SINGLE,
                    "testdb.table1",
                    ImmutableList.of("tag1", "tag2", "tag3", "count"),
                    ImmutableSet.of("tag1", "tag2", "tag3", "s2")))));

    // Output - Collect - Project - AggTableScan
    assertPlan(planTester.getFragmentPlan(0), output(collect(exchange(), exchange())));

    // Project - AggTableScan
    for (int i = 1; i <= 2; i++) {
      assertPlan(
          planTester.getFragmentPlan(i),
          project(
              aggregationTableScan(
                  singleGroupingSet("tag1", "tag2", "tag3"),
                  ImmutableList.of("tag1", "tag2", "tag3"), // Streamable
                  Optional.empty(),
                  SINGLE,
                  "testdb.table1",
                  ImmutableList.of("tag1", "tag2", "tag3", "count"),
                  ImmutableSet.of("tag1", "tag2", "tag3", "s2"))));
    }

    // All ID columns appear in GroupingKeys, and Attribute columns , time or date_bin(time) also
    // appear
    logicalQueryPlan =
        planTester.createPlan(
            "SELECT count(s2) FROM table1 group by tag1, tag2, tag3, attr1, date_bin(1h, time)");
    assertPlan(
        logicalQueryPlan,
        output(
            project(
                aggregationTableScan(
                    singleGroupingSet("tag1", "tag2", "tag3", "attr1", "date_bin$gid"),
                    ImmutableList.of("tag1", "tag2", "tag3", "attr1"), // Streamable
                    Optional.empty(),
                    SINGLE,
                    "testdb.table1",
                    ImmutableList.of("tag1", "tag2", "tag3", "attr1", "date_bin$gid", "count"),
                    ImmutableSet.of("tag1", "tag2", "tag3", "attr1", "time", "s2")))));
    // Output - Project - Agg(FINAL) - MergeSort - AggTableScan
    assertPlan(
        planTester.getFragmentPlan(0),
        output(
            project(
                aggregation(
                    singleGroupingSet("tag1", "tag2", "tag3", "attr1", "date_bin$gid"),
                    ImmutableMap.of(
                        Optional.empty(),
                        aggregationFunction("count", ImmutableList.of("count_0"))),
                    ImmutableList.of("tag1", "tag2", "tag3", "attr1"), // Streamable
                    Optional.empty(),
                    FINAL,
                    mergeSort(exchange(), exchange(), exchange())))));

    for (int i = 1; i <= 3; i++) {
      assertPlan(
          planTester.getFragmentPlan(i),
          aggregationTableScan(
              singleGroupingSet("tag1", "tag2", "tag3", "attr1", "date_bin$gid"),
              ImmutableList.of("tag1", "tag2", "tag3", "attr1"), // Streamable
              Optional.empty(),
              PARTIAL,
              "testdb.table1",
              ImmutableList.of("tag1", "tag2", "tag3", "attr1", "date_bin$gid", "count_0"),
              ImmutableSet.of("tag1", "tag2", "tag3", "attr1", "time", "s2")));
    }

    // Global Aggregation or partialPushDown Aggregation with only one deviceEntry

    // Output - AggTableScan
    assertPlan(
        planTester.createPlan("SELECT count(s2) FROM table1 where tag1='beijing' and tag2='A1'"),
        output(
            aggregationTableScan(
                singleGroupingSet(),
                ImmutableList.of(), // UnStreamable
                Optional.empty(),
                SINGLE,
                "testdb.table1",
                ImmutableList.of("count"),
                ImmutableSet.of("s2"))));

    assertPlan(
        planTester.createPlan(
            "SELECT count(s2) FROM table1 where tag1='beijing' and tag2='A1' group by tag3"),
        output(
            project(
                aggregationTableScan(
                    singleGroupingSet("tag3"),
                    ImmutableList.of("tag3"),
                    Optional.empty(),
                    SINGLE,
                    "testdb.table1",
                    ImmutableList.of("tag3", "count"),
                    ImmutableSet.of("s2", "tag3")))));
  }

  @Test
  public void syntacticSugarTest() {
    PlanTester planTester = new PlanTester();

    // First and last need to be added the second argument 'time' if it is not explicit
    LogicalQueryPlan logicalQueryPlan =
        planTester.createPlan("SELECT first(s1+1), last(s2) FROM table1");
    assertPlan(
        logicalQueryPlan,
        output(
            aggregation(
                singleGroupingSet(),
                ImmutableMap.of(
                    Optional.of("first"),
                    aggregationFunction("first", ImmutableList.of("expr", "time")),
                    Optional.of("last"),
                    aggregationFunction("last", ImmutableList.of("s2", "time"))),
                ImmutableList.of(),
                Optional.empty(),
                SINGLE,
                project(
                    ImmutableMap.of(
                        "expr",
                        expression(
                            new ArithmeticBinaryExpression(
                                ADD, new SymbolReference("s1"), new LongLiteral("1")))),
                    tableScan(
                        "testdb.table1",
                        ImmutableList.of("time", "s1", "s2"),
                        ImmutableSet.of("s1", "s2", "time"))))));
  }

  @Test
  public void withTimePushDownLevelTest() {
    PlanTester planTester = new PlanTester();

    // first, last, first_by with time, last_by with time should be push-down
    LogicalQueryPlan logicalQueryPlan =
        planTester.createPlan(
            "SELECT first(s1), last(s1), first_by(time,s1), last_by(time,s1) FROM table1 group by tag1, tag2, tag3");

    // Output - Project - AggregationTableScan
    assertPlan(
        logicalQueryPlan,
        output(
            project(
                aggregationTableScan(
                    singleGroupingSet("tag1", "tag2", "tag3"),
                    ImmutableList.of("tag1", "tag2", "tag3"), // Streamable
                    Optional.empty(),
                    SINGLE,
                    "testdb.table1",
                    ImmutableList.of(
                        "tag1", "tag2", "tag3", "first", "last", "first_by", "last_by"),
                    ImmutableSet.of("tag1", "tag2", "tag3", "s1", "time")))));
  }

  @Test
  public void deviceWithNumerousRegionTest() {
    PlanTester planTester = new PlanTester();
    LogicalQueryPlan logicalQueryPlan =
        planTester.createPlan("SELECT count(s1) FROM table1 where tag2='B2'");
    // complete push-down when do logical optimize
    assertPlan(
        logicalQueryPlan,
        output(
            aggregationTableScan(
                singleGroupingSet(),
                ImmutableList.of(),
                Optional.empty(),
                SINGLE,
                "testdb.table1",
                ImmutableList.of("count"),
                ImmutableSet.of("s1"))));

    // transform to two-stage when generate distribution plan
    assertPlan(
        planTester.getFragmentPlan(0),
        output(
            aggregation(
                singleGroupingSet(),
                ImmutableMap.of(
                    Optional.of("count"),
                    aggregationFunction("count", ImmutableList.of("count_0"))),
                Optional.empty(),
                FINAL,
                collect(exchange(), exchange()))));
    for (int i = 1; i <= 2; i++) {
      assertPlan(
          planTester.getFragmentPlan(i),
          aggregationTableScan(
              singleGroupingSet(),
              ImmutableList.of(),
              Optional.empty(),
              PARTIAL,
              "testdb.table1",
              ImmutableList.of("count_0"),
              ImmutableSet.of("s1")));
    }

    logicalQueryPlan =
        planTester.createPlan(
            "SELECT count(s1) FROM table1 where tag2='B2' group by tag1, tag2, tag3");
    // complete push-down when do logical optimize
    assertPlan(
        logicalQueryPlan,
        output(
            project(
                aggregationTableScan(
                    singleGroupingSet("tag1", "tag2", "tag3"),
                    ImmutableList.of("tag1", "tag2", "tag3"),
                    Optional.empty(),
                    SINGLE,
                    "testdb.table1",
                    ImmutableList.of("tag1", "tag2", "tag3", "count"),
                    ImmutableSet.of("tag1", "tag2", "tag3", "s1")))));

    // transform to two-stage when generate distribution plan
    assertPlan(
        planTester.getFragmentPlan(0),
        output(
            project(
                aggregation(
                    singleGroupingSet("tag1", "tag2", "tag3"),
                    ImmutableMap.of(
                        Optional.of("count"),
                        aggregationFunction("count", ImmutableList.of("count_0"))),
                    ImmutableList.of("tag1", "tag2", "tag3"),
                    Optional.empty(),
                    FINAL,
                    mergeSort(exchange(), exchange())))));
    for (int i = 1; i <= 2; i++) {
      assertPlan(
          planTester.getFragmentPlan(i),
          aggregationTableScan(
              singleGroupingSet("tag1", "tag2", "tag3"),
              ImmutableList.of("tag1", "tag2", "tag3"),
              Optional.empty(),
              PARTIAL,
              "testdb.table1",
              ImmutableList.of("tag1", "tag2", "tag3", "count_0"),
              ImmutableSet.of("tag1", "tag2", "tag3", "s1")));
    }
  }

  @Test
  public void countConstantTest() {
    PlanTester planTester = new PlanTester();

    LogicalQueryPlan ret =
        planTester.createPlan("SELECT count(*) FROM table1 where tag1='beijing' and tag2='A1'");
    assertPlan(
        ret,
        output(
            aggregationTableScan(
                singleGroupingSet(),
                ImmutableList.of(), // UnStreamable
                Optional.empty(),
                SINGLE,
                "testdb.table1",
                ImmutableList.of("count"),
                ImmutableSet.of("time"))));

    ret = planTester.createPlan("SELECT count(1) FROM table1 where tag1='beijing' and tag2='A1'");
    assertPlan(
        ret,
        output(
            aggregationTableScan(
                singleGroupingSet(),
                ImmutableList.of(), // UnStreamable
                Optional.empty(),
                SINGLE,
                "testdb.table1",
                ImmutableList.of("count"),
                ImmutableSet.of("time"))));

    ret = planTester.createPlan("SELECT count('a') FROM table1 where tag1='beijing' and tag2='A1'");
    assertPlan(
        ret,
        output(
            aggregationTableScan(
                singleGroupingSet(),
                ImmutableList.of(), // UnStreamable
                Optional.empty(),
                SINGLE,
                "testdb.table1",
                ImmutableList.of("count"),
                ImmutableSet.of("time"))));
  }
}
