C＃插入访问数据库：无错误，命令成功，但未插入数据

Question

I'm using C# (on Visual Studio 2013) with .Net 4.0 and an access 2002 database (.mdb) The data I'm trying to insert is stored in these variables:

int cantidad = int.Parse(txtCantParejas.Text);
DateTime fechaActual = DateTime.Now;
int dia = fechaActual.Day;
int mes = fechaActual.Month;
int anio = fechaActual.Year;
int hora = fechaActual.Hour;
int minuto = fechaActual.Minute;

I've built this query:

string query = "INSERT INTO Torneo (cantParejas,dia,mes,anio,hora,minuto)VALUES (@cantParejas,@dia,@mes,@anio,@hora,@minuto)";

And I have a connection string (connection test succeeds) stored in the variable "strDeConexion".

So I try to insert the data into my table:

OleDbConnection dbConnection = new OleDbConnection(strDeConexion);
OleDbCommand commandStatement = new OleDbCommand(query, dbConnection);
dbConnection.Open();
commandStatement.Parameters.Add("@cantParejas", OleDbType.Integer).Value = cantidad;
commandStatement.Parameters.Add("@dia", OleDbType.Integer).Value = dia;
commandStatement.Parameters.Add("@mes", OleDbType.Integer).Value = mes;
commandStatement.Parameters.Add("@anio", OleDbType.Integer).Value = anio;
commandStatement.Parameters.Add("@hora", OleDbType.Integer).Value = hora;
commandStatement.Parameters.Add("@minuto", OleDbType.Integer).Value = minuto;
commandStatement.ExecuteNonQuery();
dbConnection.Close();

The columns in my Access database table are all of Integer type and there is also an autoincrementing column called "idTorneo" which is the primary key and I didn't include in my query (because it's auto increment).

However, when I run my code, I get no errors (I tried wrapping the insertion in a try-catch and I see the "try" bit being executed). But when I check the data in my table, the table is empty. Since I get no errors I'm quite puzzled and don't know where to start looking. I tried inserting this way as well, with no luck:

commandStatement.CommandType = CommandType.Text;
commandStatement.Parameters.AddWithValue("cantParejas", cantidad);
commandStatement.Parameters.AddWithValue("dia", dia);
commandStatement.Parameters.AddWithValue("mes", mes);
commandStatement.Parameters.AddWithValue("anio", anio);
commandStatement.Parameters.AddWithValue("hora", hora);
commandStatement.Parameters.AddWithValue("minuto", minuto);

Any help on what could be wrong or how to investigate this issue will be appreciated :)

Answer 1

The OleDbCommand does not fully support named parameters. Use ? instead:

 string query = "INSERT INTO Torneo (cantParejas,dia,mes,anio,hora,minuto) VALUES (?, ?, ?, ?, ?, ?)";

Answer 2

Well, I found the "bug" and it was just a configuration issue I would've never imagined. I tried everything suggested here (thanks!!) and I finally decided to avoid parameters to see if that was the problem. So I converted my query to "INSERT INTO Torneo (cantParejas,dia,mes,anio,hora,minuto) VALUES ('" + cantidad + "','" + dia + "','" + mes + "','" + anio + "','" + hora + "','" + minuto + "')"; and left the code just as

OleDbConnection dbConnection = new OleDbConnection();
dbConnection.ConnectionString = strDeConexion;
dbConnection.Open();
OleDbCommand commandStatement = new OleDbCommand();
commandStatement.Connection = dbConnection;
commandStatement.CommandText = query;
commandStatement.ExecuteNonQuery();
dbConnection.Close();

However, I still was getting nothing. Until I went to my Solution Explorer, selected my database and changed the property "Copy to output directory" from "Copy always" to "Do not copy", then went to the output directory (....\\bin\\debug) and manually pasted my database file in there. Ta-da! Now THIS copy of the database is getting updated.

I could've spent the whole week debugging without even thinking of this little trick, so I wanted to post it in here in case anyone else has the same problem.