Question

所以基本上，我有2张桌子，租户和业主。我的存储过程是内部连接，以在文本框中显示选择结果。但不幸的是，查询只是从所有者表中提取而不是两者都是。尝试从租户表中显示该列不存在时出现错误。

@ID varchar(4)

SELECT        owner_table.ownerID AS ownID, tenant_table.tenantID, owner_table.apt_num AS aptNum, owner_table.first_name AS own_first, owner_table.last_name AS own_last, 
                     owner_table.address AS own_address, owner_table.city AS own_city, owner_table.state AS own_state, owner_table.zip AS own_zip, 
                     owner_table.phone AS own_phone, owner_table.phone_2 AS own_phone2, owner_table.notes AS own_notes, owner_table.last_update AS own_lastUpdate, 
                     tenant_table.ownerID AS ten_ownID, tenant_table.last_name, tenant_table.keyID, tenant_table.storage, tenant_table.phone, tenant_table.phone_2, tenant_table.notes,
                      tenant_table.complaints, tenant_table.lease_end, tenant_table.last_update, tenant_table.apt_status
FROM            owner_table INNER JOIN
                     tenant_table ON owner_table.ownerID = @ID AND tenant_table.tenantID = @ID
RETURN

代码试图从程序中获得结果。

private void LoadInfo(string ID)
    {
        using (SqlConnection connection = new SqlConnection(connectionString))
        {                           

            SqlCommand Command = new SqlCommand();
            Command.Connection = connection;
            Command.CommandText = "MoreInfoData";
            Command.CommandType = CommandType.StoredProcedure;
            Command.Parameters.Add(new SqlParameter("@ID", SqlDbType.VarChar, 4)).Value = ID;

            table = new DataTable();
            SqlDataAdapter MyAdapter = new SqlDataAdapter();
            MyAdapter.SelectCommand = Command;
            MyAdapter.Fill(table);

            if (table.Rows.Count > 0)
            {
                ten_name.Text = table.Rows[0]["last_name"].ToString();                       
            }

    }

Answer 1

修改以使用列别名：

ten_name.Text = table.Rows[0]["own_last"].ToString();

Answer 2

您将字段名称更改为own_last，因此它当然不存在。 owner_table.last_name AS own_last。所以你应该把你的代码改成

ten_name.Text = table.Rows[0]["own_last"].ToString();

Answer 3

您是否尝试为tenant_table.last_name添加别名？：

SELECT .... tenant_table.last_name AS tenant_last_name

然后：

ten_name.Text = table.Rows[0]["tenant_last_name"].ToString();

Answer 4

您是否可以运行此命令并查看输出中的内容，应列出要检索的数据表的所有列名称。

if (table.Rows.Count > 0)
{
    foreach (System.Data.DataColumn col in table.Columns)
    {
        System.Diagnostics.Debug.WriteLine(col.ColumnName);
    }
}

Answer 5

总而言之，无论如何我当时保存到我的查询中都不会因为某些原因而保存。毕竟这最终成了问题。感谢您的帮助。

SQL查询仅从一个表中提取数据

5 个答案: