[marcoszorrilla]

Código Delphi [-]
ADOConec: TADOConnection;
      ADOQyArticles: TADOQuery;
      DSarticles: TDataSource;
      ADOQyStocks: TADOQuery;
      DSstocks: TDataSource;
   
    while not ADOQyArticles.Eof do
     begin
              ADOQystocks.SQL.Clear;
              ADOQyStocks.SQL.Add('update F_ARTSTOCK ' +
                                  ' set AS_QTEMINI= :Parm_min,AS_QTEMAXI= :Parm_max ' +
                                  ' where AS_PRINCIPAL = 1 ' +
                                  ' AND AR_REF = '+ #39 + codrefe + #39
                                );
              ADOQyStocks.Parameters.ParamValues['Parm_min'] := round (dias_min * venta_dia);
              ADOQyStocks.Parameters.ParamValues['Parm_max'] := round (dias_max * venta_dia);
            ADOQyStocks.ExecSQL;
            //ADOQystocks.Active; Esto te sobra
      //si sigue dando error pon añade: AdoQyStocks.Edit;
            AdoQyStocks.Post;
         end;
        ADOQyArticles.Next;           
     end;
   
   ADOConec.CommitTrans;

Un Saludo.