获取错误 oledbexception 未处理附加信息：没有为一个或多个必需参数提供值

Question

我在尝试 select 数据库中的数据时遇到此错误，我不知道如何修复它。我的查询在我的数据库中有效，但我不确定发生了什么

randomget = "SELECT top 1 id, Department, Team, Process,  SubProcess, SubTask, LastUpdatedBy from workload where stepstatus = 'complete' and agent is null or agent = 0  ";
OleDbConnection MyConn = new OleDbConnection();
MyConn.ConnectionString = @"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=.......;Persist Security Info=False";;
MyConn.Open();
OleDbCommand cmd = MyConn.CreateCommand();
cmd.CommandText = randomget;
OleDbDataReader reader = cmd.ExecuteReader(CommandBehavior.CloseConnection);
int id = 0;

while (reader.Read())
{
    id = int.Parse(reader[0].ToString());
    textBox8.Text = reader[6].ToString();
    textBox5.Text = reader[1].ToString();
    textBox6.Text = reader[2].ToString();
    textBox7.Text = reader[3].ToString();
    textBox9.Text = reader[4].ToString();
    textBox11.Text = reader[5].ToString();
    break;
} 

// input table name here 
textBox2.Text = agentsrf.ToString();
string sqlupdate = "Update workload set agent = '" + agent + "',  where ID = "  + id + " ' ";          
}

public OleDbConnection connection { get; set; }

Answer 1

在 set agent = '" + agent + "' 之后你有一个杂散的 , 只需将其删除，然后它就可以正常工作。你也应该使用 parameterized queries because this kind of string concatenations are open for SQL Injection:

string sqlupdate = "Update workload set agent = @agent where ID = @id ";
cmd.Parameters.AddWithValue("@agent", agent );
cmd.Parameters.AddWithValue("@id", id);

Answer 2

我解决了。我的一个字段名称中有一个 space，我没有发现它。

获取错误 oledbexception 未处理附加信息：没有为一个或多个必需参数提供值

getting a error oledbexception was unhandled Additional information: No value given for one or more required parameters

.net

c#

sql

oledb