Question

I have that code :

string query = "select count(*) 
                  from MODEL m 
                  join KOLEKCJA ko on m.SEZON = ko.sezon 
             left join PRODUCENCI p on p.PRODUCENT_ID = m.PRODUCENT_ID 
             left join KRAJ k on k.KOD = m.KRAJ_POCH 
                 where ko.SEZON like :ko.SEZON 
                   and m.DO_PRODUKCJI like :m.DO_PRODUKCJI 
                   and k.KOD like :KOD 
                   and p.PRODUCENT_ID like :PRODUCENT_ID 
                   and m.MODEL_ID like :MODEL_ID";

OdbcCommand comm = new OdbcCommand();
comm.Connection = con;
comm.CommandText = query;
comm.CommandType = CommandType.Text;
comm.Parameters.AddWithValue("ko.SEZON", sezon);
comm.Parameters.AddWithValue("m.DO_PRODUKCJI", do_produkcji);
comm.Parameters.AddWithValue("KOD", kraj);
comm.Parameters.AddWithValue("PRODUCENT_ID", fabryka);
comm.Parameters.AddWithValue("MODEL_ID", model);

result = (int)comm.ExecuteScalar();

and always have error that parameters are not changed ;/
What do I wrong ?

Answer 1

ODBC connections do not work with named placeholders like the other connection types do. ODBC uses positional parameters marked by a question mark (?). Replace your bind variables with question marks and be sure to add your parameters in the correct order. The parameter name you pass to AddWithValue() can be anything. Like so:

string query = "select count(*) 
                  from MODEL m 
                  join KOLEKCJA ko on m.SEZON = ko.sezon 
             left join PRODUCENCI p on p.PRODUCENT_ID = m.PRODUCENT_ID 
             left join KRAJ k on k.KOD = m.KRAJ_POCH 
                 where ko.SEZON       like ? 
                   and m.DO_PRODUKCJI like ? 
                   and k.KOD          like ? 
                   and p.PRODUCENT_ID like ? 
                   and m.MODEL_ID     like ?";

OdbcCommand comm = new OdbcCommand();
comm.Connection = con;
comm.CommandText = query;
comm.CommandType = CommandType.Text;
comm.Parameters.AddWithValue("ko.SEZON", sezon);
comm.Parameters.AddWithValue("m.DO_PRODUKCJI", do_produkcji);
comm.Parameters.AddWithValue("KOD", kraj);
comm.Parameters.AddWithValue("PRODUCENT_ID", fabryka);
comm.Parameters.AddWithValue("MODEL_ID", model);

result = (int)comm.ExecuteScalar();