从数据库表添加数据类型

我有一个SQL数据库表，我正在从我的c#项目中查询。该表包含一列，该列将 int 作为数据类型（雇主年龄）。我正在从此列进行查询，我希望将从此列查询的每条记录相加并显示记录总数;

法典：

int AddAge;
string getAge;
    Query = "SELECT * FROM TblEmp WHERE Id = '" + id + "' AND Position = '"+Manager+"'";
                       theReader = conn.ExecuteStatement(Query);
                       while(theReader.Read())
                       getAge = theReader["Age"].ToString();
                       AddAge = int.Parse(getAge);

                     AddAge + getAge; // this is where i am stuck, How can I add up the ages and display the the total?

while(theReader.Read())
{
                       getAge = theReader["Age"].ToString();
                       AddAge = int.Parse(getAge);

                     AddAge + getAge;
}

Query = "SELECT SUM(Age) FROM TblEmp WHERE Id = '" + id + "' AND Position = '"+Manager+"'";