CODEWITHSUNDEEP
vb.net
user3048626
user3048626

Reputation: 1

I m trying to fetch total in to TextBox5.text but error occured

I m trying to fetch total in to TextBox5.text but error occured like No value given for one or more required parameters.

Try con.Close()

        con.ConnectionString = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=Pradnya_DataB.mdb"

        con.Open()

        ss = "Select total from stock_bottle WHERE Bottle_type=" & Convert.ToString(TextBox3.Text.ToString())

        cmd = New OleDbCommand(ss, con)

        rd = cmd.ExecuteReader()

        If rd.Read() Then

            TextBox5.Text = rd("total").ToString()

        End If

        con.Close()
        rd.Close()


    Catch ex As Exception
        MsgBox(ex.Message)
    End Try

Upvotes: 0

Views: 16

Answers (1)

Steve
Steve

Reputation: 216253

This error occurs when one or more of your column names and table name are not spelled correctly. In your case, this means that Total or Bottle_type or even Stock_Bottle are not the correct name for your fields or table.

Saying that, and pending the due correction to your query, I suggest you to use a more robust code like this one

Try
    Dim ss = "Select total from stock_bottle WHERE Bottle_type=@btype"
    Using con = new OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=Pradnya_DataB.mdb")
    Using cmd = new OleDbCommand(ss, con)
        con.Open()
        cmd.Parameters.Add("@btype", OleDbType.Int32).Value = TextBox3.Text
        Dim result = cmd.ExecuteScalar()
        If result IsNot Nothing Then
            TextBox5.Text = result.ToString()
        End If
    End Using
    End Using
Catch ex As Exception
    MsgBox(ex.Message)
End Try

Here I have changed your query to a parameterized query. It is more safe and robust about the correct interpretation of the DataType used for your where clause. I have also removed the global variable for the connection. (You don't get any advantage and you need to constantly check for the status of that connection).
I have added the Using statement to ensure proper closing of connection and the immediate release of the system resources kept by the connection.

Finally, if you need to retrieve just one row with one single column then do not use the more expensive OleDbDataReader (useful when there are many rows and columns to read back) but directly the OleDbCommand with its ExecuteScalar method

Upvotes: 1

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