求一句SQL

Question

department表中的departmentid根据newdepartment进行更新~
String StrUpDate = "update departmentid from department where departmentid='" + NewDepartment+"'";
上面是小菜我写的,求高手帮我~~~

Answer 1

"update departmentid from department where departmentid='" + NewDepartment;

Answer 2

"update departmentid from department where departmentid=" + NewDepartment;

Answer 3

UPDATE department 
SET departmentid =NewDepartment
where ...

Answer 4

忘了说了,NewDepartment是一个定义好的变量,根据teacherId应该怎么写呢?~

Answer 5

string updateSQL="UPDATE department SET departmentid='"+NewDepartment+"' WHERE departmentid='"+teacherId+"'"

Answer 6

TextBox myTeacherId = DetailsViewMove.FindControl("TextBoxTeacherId") as TextBox;
        if (myTeacherId != null)
        {
            String StrTeacherId = "UPDATE department SET departmentid =" + NewDepartment + "where TeacherId='" + myTeacherId.Text + "'";
            SqlCommand myCommand2 = new SqlCommand(StrTeacherId, myConnection);
            SqlDataReader myReader2 = myCommand2.ExecuteReader();
            
        }现在只是能读出来!

Answer 7

string updateSQL="UPDATE department SET departmentid='"+NewDepartment+"' WHERE departmentid='"+teacherId+"'"
SqlCommand sqlcmd = new SqlCommand(StrTeacherId, myConnection);
sqlcmd.ExecuteNonQuery();

Answer 8

SqlCommand myCommand2=myConnection.CreateCommand();
myCommand2.CommandText=StrTeacherId;
myCommand2.ExecuteNonQuery();

Answer 9

TextBox myTeacherId = DetailsViewMove.FindControl("TextBoxTeacherId") as TextBox;
        if (myTeacherId != null)
        {
            String StrTeacherId = "UPDATE department SET departmentid =" + NewDepartment + " where TeacherId='" + myTeacherId.Text + "'";
            SqlCommand myCommand2 = myConnection.CreateCommand();
            myCommand2.CommandText = StrTeacherId;
            myCommand2.ExecuteNonQuery();
            //SqlCommand sqlcmd = new SqlCommand(StrTeacherId, myConnection);
            //sqlcmd.ExecuteNonQuery();        }
为什么出错啊?提示TeacherId无效,查看详细是应为where后面的TeacherId 是空.为什么?有高手知道么?

Answer 10

估计是，你打字的过程中，有多余的空格。sql对于空格很敏感。
建议对代码中间的空格都检查一遍，注意一下全半角，还有单引号。

Answer 11

看过myTeacherId.Text里有没有东西吗?