Question

As the code Shows below, I want to insert a row into a database table (oracle 11) and return a String-Value of the inserted row.

using (OracleCommand cmd = con.CreateCommand()) {
    cmd.CommandText = "insert into foo values('foo','bar') returning idString into :lastIdParam";
    cmd.Parameters.Add(new OracleParameter("lastIdParam", OracleDbType.Varchar2), ParameterDirection.ReturnValue);
    cmd.ExecuteNonQuery();  // returning 1 (insert row successfully)

    var result = cmd.Parameters["lastIdParam"].Value.ToString();   // == String.Empty
}

Debugging shows that lastIdParam.Value’s value = Empty.String:

My Problem is, that I’m not getting the return string into my return-parameter but it will work when returning an integer value (like sequence no of inserted id). Cast Problem? …?

The idString is filled if running the Statement directly (or if I just do something like returning 'ABC' into :myOutputParameter

Any ideas how to retrieve a string after inserting row?

Answer 1

Have you tried setting a size for the parameter? The default size is 0.

new OracleParameter("lastIdParam", OracleDbType.Varchar2, 128)