Question

I have three fields called fileName,rowNo and rowText in Access 07 table named shortNotes.
When I run this insert query it works perfect:

thisCommand.CommandText = “insert into shortNotes values(‘” + fName + “‘,” + rNo + “,'” + richTextBox2.Text +” |”+rNo+ “‘)”;

But when I added parameters, It started throwing this error:
“data type mismatch in Criteria Expression”

Here is the code:

        dbCon = new OleDbConnection(MyconnectionString);
        dbCon.Open();
        thisCommand = new OleDbCommand();
        thisCommand.Connection = dbCon;

        thisCommand.Parameters.Add("@rowtext", OleDbType.BSTR);
        thisCommand.Parameters.Add("@file", OleDbType.BSTR);
        thisCommand.Parameters.Add("@rno", OleDbType.Integer);

        thisCommand.Parameters["@rowtext"].Value = richTextBox2.Text + " |" + rNo;

        thisCommand.Parameters["@file"].Value = fName;

        thisCommand.Parameters["@rno"].Value = rNo;

        thisCommand.CommandText = "insert into shortNotes values(@file,@rno,@rowtext)";
        thisCommand.ExecuteNonQuery();//Error 

Here file is memo, rno is number and rowtext is memo datatype in access 07.
What is the problem?

Answer 1

The problem is OleDb does NOT use named parameters.

“The OLE DB.NET Framework Data Provider uses positional parameters that are marked with a question mark (?) instead of named parameters.”

http://msdn.microsoft.com/en-us/library/system.data.oledb.oledbparameter.aspx

Check the example there..