@Test
  public void testDecimalScalarModuloDecimalColumn() throws HiveException {
    VectorizedRowBatch b = getVectorizedRowBatch3DecimalCols();
    HiveDecimal d = HiveDecimal.create("2.00");
    VectorExpression expr = new DecimalScalarModuloDecimalColumn(d, 0, 2);

    // test without nulls
    expr.evaluate(b);
    DecimalColumnVector r = (DecimalColumnVector) b.cols[2];
    assertTrue(r.vector[0].getHiveDecimal().equals(HiveDecimal.create("0.80")));
    assertTrue(r.vector[1].getHiveDecimal().equals(HiveDecimal.create("2.00")));
    assertFalse(r.noNulls); // entry 2 will be null due to zero-divide
    assertTrue(r.isNull[2]);

    // try again with some different data values
    DecimalColumnVector in = (DecimalColumnVector) b.cols[0];
    expr = new DecimalScalarModuloDecimalColumn(d, 0, 2);
    in.vector[0].set(HiveDecimal.create("0.50"));
    in.vector[1].set(HiveDecimal.create("0.80"));
    in.vector[2].set(HiveDecimal.create("0.70"));

    expr.evaluate(b);
    assertTrue(r.vector[0].getHiveDecimal().equals(HiveDecimal.create("0.00")));
    assertTrue(r.vector[1].getHiveDecimal().equals(HiveDecimal.create("0.40")));
    assertTrue(r.vector[2].getHiveDecimal().equals(HiveDecimal.create("0.60")));
  }
Unit tests for vectorized arithmetic expressions.
ql/src/test/org/apache/hadoop/hive/ql/exec/vector/expressions/TestVectorArithmeticExpressions.java