public SqlType getExpressionSqlType(final Expression expression) {
    return getExpressionSqlType(expression, Collections.emptyMap());
  }
@Test
  public void testComparisonExpr() {
    final Expression expression = new ComparisonExpression(Type.GREATER_THAN, TestExpressions.COL0,
        COL3
    );

    final SqlType exprType = expressionTypeManager.getExpressionSqlType(expression);

    assertThat(exprType, is(SqlTypes.BOOLEAN));
  }