content: /*
   * 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.beam.sdk.extensions.sql;
  
  import static org.apache.beam.sdk.extensions.sql.utils.RowAsserts.matchesNull;
  import static org.apache.beam.sdk.extensions.sql.utils.RowAsserts.matchesScalar;
  import static org.junit.Assert.assertEquals;
  
  import java.util.List;
  import org.apache.beam.sdk.schemas.Schema;
  import org.apache.beam.sdk.testing.PAssert;
  import org.apache.beam.sdk.testing.TestPipeline;
  import org.apache.beam.sdk.transforms.Create;
  import org.apache.beam.sdk.values.PBegin;
  import org.apache.beam.sdk.values.PCollection;
  import org.apache.beam.sdk.values.Row;
  import org.junit.Before;
  import org.junit.Rule;
  import org.junit.Test;
  
  /** Integration tests for aggregation nullable columns. */
  public class BeamSqlDslAggregationNullableTest {
  
    @Rule public TestPipeline pipeline = TestPipeline.create();
  
    private PCollection<Row> boundedInput;
  
    @Before
    public void setUp() {
      Schema schema =
          Schema.builder()
              .addNullableField("f_int1", Schema.FieldType.INT32)
              .addNullableField("f_int2", Schema.FieldType.INT32)
              .addInt32Field("f_int3")
              .build();
  
      List<Row> rows =
          TestUtils.RowsBuilder.of(schema)
              .addRows(1, 5, 1)
              .addRows(null, 1, 1)
              .addRows(2, 1, 1)
              .addRows(null, 1, 1)
              .addRows(null, null, 1)
              .addRows(null, null, 1)
              .addRows(3, 2, 1)
              .getRows();
  
      boundedInput = PBegin.in(pipeline).apply(Create.of(rows).withRowSchema(schema));
    }
  
    @Test
    public void testCount() {
      String sql = "SELECT COUNT(f_int1) FROM PCOLLECTION GROUP BY f_int3";
  
      PAssert.that(boundedInput.apply(SqlTransform.query(sql))).satisfies(matchesScalar(3L));
  
      pipeline.run();
    }
  
    @Test
    public void testCountNull() {
      String sql = "SELECT COUNT(f_int1) FROM PCOLLECTION WHERE f_int2 IS NULL GROUP BY f_int3";
  
      PAssert.that(boundedInput.apply(SqlTransform.query(sql))).satisfies(matchesScalar(0L));
  
      pipeline.run();
    }
  
    @Test
    public void testCountStar() {
      String sql = "SELECT COUNT(*) FROM PCOLLECTION GROUP BY f_int3";
  
      PAssert.that(boundedInput.apply(SqlTransform.query(sql))).satisfies(matchesScalar(7L));
  
      pipeline.run();
    }
  
    @Test
    public void testCountThroughSum() {
      String sql =
          "SELECT SUM(CASE f_int1 IS NOT NULL WHEN TRUE THEN 1 ELSE 0 END) "
              + "FROM PCOLLECTION GROUP BY f_int3";
  
      PAssert.that(boundedInput.apply(SqlTransform.query(sql))).satisfies(matchesScalar(3));
  
      pipeline.run();
    }
  
    @Test
    public void testCountNulls() {
      String sql =
          "SELECT SUM(CASE f_int1 IS NULL WHEN TRUE THEN 1 ELSE 0 END) "
              + "FROM PCOLLECTION GROUP BY f_int3";
  
      PAssert.that(boundedInput.apply(SqlTransform.query(sql))).satisfies(matchesScalar(4));
  
      pipeline.run();
    }
  
    @Test
    public void testSum() {
      String sql = "SELECT SUM(f_int1) FROM PCOLLECTION GROUP BY f_int3";
  
      PAssert.that(boundedInput.apply(SqlTransform.query(sql))).satisfies(matchesScalar(6));
  
      pipeline.run();
    }
  
    @Test
    public void testSumNull() {
      String sql = "SELECT SUM(f_int1) FROM PCOLLECTION WHERE f_int2 IS NULL GROUP BY f_int3";
  
      PAssert.that(boundedInput.apply(SqlTransform.query(sql))).satisfies(matchesNull());
  
      pipeline.run();
    }
  
    @Test
    public void testMin() {
      String sql = "SELECT MIN(f_int1) FROM PCOLLECTION GROUP BY f_int3";
  
      PAssert.that(boundedInput.apply(SqlTransform.query(sql))).satisfies(matchesScalar(1));
  
      pipeline.run();
    }
  
    @Test
    public void testMinNull() {
      String sql = "SELECT MIN(f_int1) FROM PCOLLECTION WHERE f_int2 IS NULL GROUP BY f_int3";
  
      PAssert.that(boundedInput.apply(SqlTransform.query(sql))).satisfies(matchesNull());
  
      pipeline.run();
    }
  
    @Test
    public void testMax() {
      String sql = "SELECT MAX(f_int1) FROM PCOLLECTION GROUP BY f_int3";
  
      PAssert.that(boundedInput.apply(SqlTransform.query(sql))).satisfies(matchesScalar(3));
  
      pipeline.run();
    }
  
    @Test
    public void testMaxNull() {
      String sql = "SELECT MAX(f_int1) FROM PCOLLECTION WHERE f_int2 IS NULL GROUP BY f_int3";
  
      PAssert.that(boundedInput.apply(SqlTransform.query(sql))).satisfies(matchesNull());
  
      pipeline.run();
    }
  
    @Test
    public void testAvg() {
      String sql = "SELECT AVG(f_int1) FROM PCOLLECTION GROUP BY f_int3";
  
      PAssert.that(boundedInput.apply(SqlTransform.query(sql))).satisfies(matchesScalar(2));
  
      pipeline.run();
    }
  
    @Test
    public void testAvgNull() {
      String sql = "SELECT AVG(f_int1) FROM PCOLLECTION WHERE f_int2 IS NULL GROUP BY f_int3";
  
      PAssert.that(boundedInput.apply(SqlTransform.query(sql))).satisfies(matchesNull());
  
      pipeline.run();
    }
  
    @Test
    public void testAvgGroupByNullable() {
      String sql = "SELECT AVG(f_int1), f_int2 FROM PCOLLECTION GROUP BY f_int2";
  
      PCollection<Row> out = boundedInput.apply(SqlTransform.query(sql));
      Schema schema = out.getSchema();
  
      PAssert.that(out)
          .containsInAnyOrder(
              Row.withSchema(schema).addValues(null, null).build(),
              Row.withSchema(schema).addValues(2, 1).build(),
              Row.withSchema(schema).addValues(1, 5).build(),
              Row.withSchema(schema).addValues(3, 2).build());
  
      pipeline.run();
    }
  
    @Test
    public void testCountGroupByNullable() {
      String sql = "SELECT COUNT(f_int1) as c, f_int2 FROM PCOLLECTION GROUP BY f_int2";
  
      PCollection<Row> out = boundedInput.apply(SqlTransform.query(sql));
      Schema schema = out.getSchema();
  
      PAssert.that(out)
          .containsInAnyOrder(
              Row.withSchema(schema).addValues(0L, null).build(),
              Row.withSchema(schema).addValues(1L, 1).build(),
              Row.withSchema(schema).addValues(1L, 5).build(),
              Row.withSchema(schema).addValues(1L, 2).build());
  
      assertEquals(
          Schema.builder()
              // COUNT() is never nullable, and calcite knows it
              .addInt64Field("c")
              .addNullableField("f_int2", Schema.FieldType.INT32)
              .build(),
          schema);
  
      pipeline.run();
    }
  
    @Test
    public void testSampleVariance() {
      // a special case of aggregator with two parameters
      String sql = "SELECT COVAR_SAMP(f_int1, f_int2) FROM PCOLLECTION GROUP BY f_int3";
  
      // COVAR_SAMP(f_int1, f_int2) =
      //   (SUM(f_int1 * f_int2) - SUM(f_int1) * SUM(f_int2) / n) / (n-1) =
      //   (SUM([1 * 5, 2 * 1, 3 * 2]) - SUM([1, 2, 3]) * SUM([5, 1, 2]) / 3) / 2 =
      //   -1.5
  
      PAssert.that(boundedInput.apply(SqlTransform.query(sql))).satisfies(matchesScalar(-1));
  
      pipeline.run();
    }
  
    @Test
    public void testSampleVarianceReverse() {
      String sql = "SELECT COVAR_SAMP(f_int2, f_int1) FROM PCOLLECTION GROUP BY f_int3";
  
      PAssert.that(boundedInput.apply(SqlTransform.query(sql))).satisfies(matchesScalar(-1));
  
      pipeline.run();
    }
  }
  