Firebird connection problem
lazarus / 16-Databases

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xinyiman · 2015-05-27 08:44

Hello guys, I have the following problem. On Linux 32-bit'm creating a
server with tcp synapse. Until everything is right. But my server has
to work also with firebird here and use the TibConnection. Now if I
run the code once no problem, but when rieseguo the code a second time
to be in error.

I realized it must be linked to the CharSet TibConnection. Who
explains to me how to solve? thanks

Code: [Select]function TTCPEchoThrd.ApriConnessioneAlDB(var Conn:
TIBConnection; var Tran: TSQLTransaction; MyHostName: string;
MyDataBaseName: string; MyUserName: string; MyPassword: string; var
MsgError: string): boolean;
var
   ret: boolean;
begin
       try
          try
            ret:=true;
            //Conn.CharSet:='disabled'; //non esiste, ma almeno mi
evita l'errore che mi fa saltare il db
            Conn.HostName:=MyHostName;
            Conn.DatabaseName:=MyDataBaseName;
            Conn.UserName:=MyUserName;
            Conn.Password:=MyPassword;
            Conn.Transaction:=Tran;
            Conn.Open;
            Tran.Active:=true;
            //ho ottenuto la connessione al database
          finally
                 //codice da effettuare a fine procedura sia che va
bene il codice sopra sia che il codice ha sollevato un'eccezzione
         end;
       except
             on E: Exception do
             begin
                MsgError:=E.Message;
                ret:=false;
             end;
       end;
       result:=ret;
end;

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xinyiman · 2015-05-27 10:10

The strange thing is that if I run the code from the IDE I have no
problem. If you launch it from the terminal / console goes wrong.

An unhandled exception occurred at $B65975F5 :
EAccessViolation : Access violation
  $B65975F5

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rvk · 2015-05-27 10:56

I don't think we have enough code.

Does that "unhandled exception" occur in that piece of code? (you
could do some logging to see if it's really there and on what line)

Where do you call ApriConnessioneAlDB and is Conn properly created?
etc... etc...

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xinyiman · 2015-05-27 12:27

I think the problem is there, why comment if the piece of code there
is no problem. The problem is that it is gentle enough for a project
and I can not copy and paste all.

If anything, if anyone is interested to help me make a support session
on my pc

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taazz · 2015-05-27 14:52

Quote from: xinyiman on May 27, 2015, 12:10:26 pmThe strange thing is
that if I run the code from the IDE I have no problem. If you launch
it from the terminal / console goes wrong.

An unhandled exception occurred at $B65975F5 :
EAccessViolation : Access violation
  $B65975F5
1) how do you run the code from the IDE? (opening the connection with
the same paramas does not execute the code).
2) are you sure that the Conn is created when that procedure is
called?

Where is that object placed at design time is the container created in
any way?

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xinyiman · 2015-05-28 11:22

Where the appeal procedure offending. As you can see you make the
connection
Code: [Select]function TTCPEchoThrd.UtenteAbilitato(NomeUtente:
string; Id_Utente: string):boolean;
var
   Conn: TIBConnection;
   Tran: TSQLTransaction;
   Query: TSQLQuery;
   ErrMes: string;
   ret: boolean;
begin
       try
          try
             Conn:=TIBConnection.Create(nil);
             Tran:=TSQLTransaction.Create(nil);
             if (Self.ApriConnessioneAlDB(Conn,Tran,'127.0.0.1','/DB/d
b.fdb','user','pwd',ErrMes)=true) then
              begin
                   ret:=false;
                   Self.CredenzialiOK:=false;
                   Self.Log('                               
CONNESSIONE AL DB EFFETTUATA');
                   Query:=TSQLQuery.Create(nil);
                   Query.DataBase:=Conn;
                   Query.SQL.Text:='select PATH from T_User WHERE
ID=:Id and Nome=:User';
                   Query.Params.ParamByName('Id').AsInteger :=
StrToInt(Id_Utente);
                   Query.Params.ParamByName('User').AsString :=
NomeUtente;
                   Query.Open;
                   if not Query.EOF then
                   begin
                        Query.First;
                        Self.DataBaseDellUtenteRemoto:=Trim(Query.Fiel
dByName('PATH').AsString);
                        if ((Length(Self.DataBaseDellUtenteRemoto)>0)
and (FileExists(Self.DataBaseDellUtenteRemoto))) then
                        begin
                           ret:=true;
                           Self.CredenzialiOK:=true;
                        end;
                   end;
                   Query.Close;
                   Query.Free;
                   Self.ChiudiConnessioneAlDB(Conn,Tran,ErrMes);
                   Self.Log('                               
CONNESSIONE AL DB CHIUSA');
              end
              else
              begin
                   Self.Log('ERRORE ' + ErrMes);
              end;
          finally
                 //codice da effettuare a fine procedura sia che va
bene il codice sopra sia che il codice ha sollevato un'eccezzione
            Tran.Free;
            Conn.Free;
         end;
       except
             on E: Exception do
             begin
                ret:=false;
                Self.Log('ERRORE ' + E.Message);
             end;
       end;
       result:=ret;
end;