[Firebird-net-provider] BeginTransaction problem??

[Thomas <ja...@ma...>]

Hi Carlos

Now I have re-created the problem.

This log line:=20
Console.WriteLine(eb.Message + " - " + eb.Source + " - " + eb.StackTrace =
+ " - " + eb.InnerException);

prints this message:
21:54:56.140 - Message: Object reference not set to an instance of an =
object. - Stacktrace:    at =
FirebirdSql.Data.Firebird.Gds.GdsTransaction.BeginTransaction()  at =
FirebirdSql.Data.Firebird.FbTransaction.BeginTransaction()    at =
FirebirdSql.Data.Firebird.FbConnection.BeginTransaction()    at =
Tricon.Funki.PDBServer.DataAccessLogicComponents.LoadStatements.loadAllSc=
aleHavePipe() in =
c:\vss\funki\pdbserver\tricon.funki.pdbserver\dataaccesslogiccomponents\l=
oadstatements.cs:line 2509 -  Source: FirebirdSql.Data.Firebird - =
InnerException:

(The InnerException is empty.)


In this test case, the same code runs 288 times.
In loop 289 the exception arised.



My code:

(loadAllScaleHavePipe() failed in loop no. 289.)



public Hashtable loadAllScaleHavePipe()
  {
   ScaleHavePipe scalehavepipe =3D null;
   Hashtable HT =3D new Hashtable();
  =20
   myConnection =3D Connection.Instance.MyConnection;

   mySelectQuery =3D "SELECT * FROM scalehavepipe";

   try
   {         =20
    transaction =3D myConnection.BeginTransaction();  <---- ERROR ?
    myCommand =3D new FbCommand(mySelectQuery, myConnection, =
transaction);       =20
    myReader =3D myCommand.ExecuteReader();
   =20
    while (myReader.Read())
    {
     scalehavepipe =3D new =
ScaleHavePipe((int)myReader["id"],(int)myReader["scaletype"],
      (int)myReader["scale_id"],(int)myReader["pipe_id"]);

     HT.Add(scalehavepipe.Id, scalehavepipe);
    }//while
    myReader.Close();=20
    transaction.Commit();
   }
   catch(Exception eb)
   {   =20
    Console.WriteLine(eb.Message + " - " + eb.Source + " - " + =
eb.StackTrace + " - " + eb.InnerException);
    BusinessComponents.LogToFile.Instance.logALineToFile(eb.Message + " =
- " + eb.Source + " - " + eb.StackTrace + " - " + =
eb.InnerException,true);

    if (eb is FbException)
    {
     FbException myException =3D (FbException)eb;    =20
     BusinessComponents.LogToFile.Instance.logALineToFile("This is a =
FbException: Message: "+myException.Message + " - Stacktrace: " + =
myException.StackTrace + " -  Source: " +myException.Source + " - =
InnerException:" + myException.InnerException + " - ErrorCode: " + =
myException.ErrorCode,true);
     Console.WriteLine("This is a FbException: Message: =
"+myException.Message + " - Stacktrace: " + myException.StackTrace + " - =
 Source: " +myException.Source + " - InnerException:" + =
myException.InnerException + " - ErrorCode: " + myException.ErrorCode);
     if (myException.Errors.Count =3D=3D 0)
     {
      =
BusinessComponents.LogToFile.Instance.logALineToFile("myException.Errors.=
Count is 0 ",true);
     }
     for (int i=3D0; i < myException.Errors.Count; i++)
     {     =20
      BusinessComponents.LogToFile.Instance.logALineToFile("Index #" + i =
+ "\n" +"Error: " + myException.Errors[i].ToString() + "\n",true);     =20
     }
    =20
    }
    else
    {    =20
     BusinessComponents.LogToFile.Instance.logALineToFile("Message: =
"+eb.Message + " - Stacktrace: " + eb.StackTrace + " -  Source: " =
+eb.Source + " - InnerException:" + eb.InnerException,true);
     Console.WriteLine("Message: "+eb.Message + " - Stacktrace: " + =
eb.StackTrace + " -  Source: " +eb.Source + " - InnerException:" + =
eb.InnerException);
    }
    Connection.Instance.closeConnection();
    Connection.Instance.openConnection();
    throw eb;
   }//try/catch
   return HT;
  }//loadAllScaleHavePipe
 =20
 =20
 =20
 =20
    public FbConnection MyConnection
    {
     get
     {  =20
      try
      {
       if (this.connectionCounter > 500)
       {
        if (this.myConnection !=3D null)
        {
         myConnection.Dispose();
         myConnection =3D new FbConnection(myConnectionString);
         openConnection();
         this.connectionCounter =3D 0;
        }//if
       }//if    =20
       else
       {              =20
        if (this.myConnection !=3D null)
        {
         closeConnection();
        }//if
        openConnection();
        this.connectionCounter =3D this.connectionCounter+1;
       }//else    =20
      }//try
      catch (Exception eb)
      {    =20
  =20
       if (eb is FbException)
       {
        FbException myException =3D (FbException)eb;    =20
        BusinessComponents.LogToFile.Instance.logALineToFile("This is a =
FbException: Message: "+myException.Message + " - Stacktrace: " + =
myException.StackTrace + " -  Source: " +myException.Source + " - =
InnerException:" + myException.InnerException + " - ErrorCode: " + =
myException.ErrorCode,true);
        Console.WriteLine("This is a FbException: Message: =
"+myException.Message + " - Stacktrace: " + myException.StackTrace + " - =
 Source: " +myException.Source + " - InnerException:" + =
myException.InnerException + " - ErrorCode: " + myException.ErrorCode);
        if (myException.Errors.Count =3D=3D 0)
        {
         =
BusinessComponents.LogToFile.Instance.logALineToFile("myException.Errors.=
Count is 0 ",true);
        }
        for (int i=3D0; i < myException.Errors.Count; i++)
        {     =20
         BusinessComponents.LogToFile.Instance.logALineToFile("Index #" =
+ i + "\n" +"Error: " + myException.Errors[i].ToString() + "\n",true);   =
  =20
        }
      =20
       }
       else
       {    =20
        BusinessComponents.LogToFile.Instance.logALineToFile("Message: =
"+eb.Message + " - Stacktrace: " + eb.StackTrace + " -  Source: " =
+eb.Source + " - InnerException:" + eb.InnerException,true);
        Console.WriteLine("Message: "+eb.Message + " - Stacktrace: " + =
eb.StackTrace + " -  Source: " +eb.Source + " - InnerException:" + =
eb.InnerException);
       }
 =20
      }//try/catch
      return this.myConnection;
     }//get =20
  }//property myConnection



I cannot see why a "Object reference not set to an instance of an =
object" should come after 288 loops.



Thanks

Regards
Thomas

-------------------------------------------------------------------------=
-------------------------------------------------------------------------=
--------------------------------------------------------


Now and then we get an exception in "BeginTrancaction".

When I call BeginTransaction(), then I get this error:

at FirebirdSql.Data.Firebird.Gds.GdsTransaction.BeginTransaction()
   at FirebirdSql.Data.Firebird.FbTransaction.BeginTransaction()
   at FirebirdSql.Data.Firebird.FbConnection.BeginTransaction()



(That is all the info that I get)


Some times the exception arise after 5 minutes, and some times the =
exception arise after 30 hours.
Very very random.


It is very hard to re-create the error, but it is 100% sure that the =
error arise at some point.

In my program, I call "myConnection.BeginTransaction()" once every 3 =
second.
(Many hours).


We use:
WinXP SP1
FirebirdSql.Data.Firebird.dll v. 1.5.1437.22333 (.NET 1.1)
Firebird-1.5.0.4027-RC7, running af Super Server.
Microsoft .NET Framework 1.1 v. 1.1.4322


Hope that you can help me with this problem.


Thanks

Regards
Thomas




/// Code snip//////

(It is impossible to send the full code)

My Connection Class that is a singleton:


........................
private FbConnection myConnection;


public static Connection Instance
  {
   get
   {             =20
    if(instance =3D=3D null)
    {
     instance =3D new Connection();    =20
    }//if
    return instance;
   }//get property
  }//property get instance of Connection
 =20

   //constructor
    private Connection()
    {
     try
     {
      myConnectionString =3D getURLToDB();
      myConnection =3D new FbConnection(myConnectionString);      =20
      openConnection();
     }//try
     catch (Exception ex)
     {
      string t =3D ex.Message;
      string t2 =3D ex.StackTrace;
      =
BusinessComponents.LogToFile.Instance.logALineToFile(ex.ToString(),true);=

     }//try/catch
  }//constructor
 =20
 =20
 =20
 public bool updateTransaction(string myUpdateQuery)
  {
   try
   {
    myConnection =3D MyConnection;
    transaction =3D myConnection.BeginTransaction();

    myCommandOne =3D new FbCommand(myUpdateQuery, myConnection, =
transaction);=20
    myCommandOne.ExecuteNonQuery();

    transaction.Commit();
    myCommandOne.Dispose();
   }
   catch(Exception eb)
   {  =20
  =20
    =
BusinessComponents.LogToFile.Instance.logALineToFile(eb.StackTrace,true);=

    BusinessComponents.LogToFile.Instance.logALineToFile("This =
SQL-statement was not saved in the database: " + myUpdateQuery,false);
    string t =3D eb.StackTrace;
    transaction.Rollback();
    transaction.Dispose();
    closeConnection();
    openConnection();
    throw eb;
   }//try/catch
   return true;
  }//updateTransaction
 =20
 =20
 =20
  public void closeConnection()
    {
     try
     {
      if (myConnection.State !=3D System.Data.ConnectionState.Closed)
      {
       myConnection.Close();  =20
      }//if
     }//try
     catch (Exception ex)
     { =20
      =
BusinessComponents.LogToFile.Instance.logALineToFile(ex.ToString(),true);=
=20
      Console.WriteLine(ex.Message);
      Console.WriteLine(ex.StackTrace);
     }//try/catch
  }//closeConnection
 =20
 =20

    public void openConnection()
    {
     try
     {
      if (myConnection.State !=3D System.Data.ConnectionState.Open)
      {
       myConnection.Open();
      }//if
     }//try
     catch(Exception ex)
     { =20
      =
BusinessComponents.LogToFile.Instance.logALineToFile(ex.ToString(),true);=
=20
      Console.WriteLine(ex.Message);
      Console.WriteLine(ex.StackTrace);
     }//try/catch
  }//openConnection
 =20
 =20
   public FbConnection MyConnection
    {
     get
     {  =20
      try
      {
       if (this.connectionCounter > 500)
       {
        if (this.myConnection !=3D null)
        {
         myConnection.Dispose();
         myConnection =3D new FbConnection(myConnectionString);
         openConnection();
         this.connectionCounter =3D 0;
        }//if
       }//if    =20
       else
       {              =20
        if (this.myConnection !=3D null)
        {
         closeConnection();
        }//if
        openConnection();
        this.connectionCounter =3D this.connectionCounter+1;
       }//else    =20
      }//try
      catch (Exception ex)
      {    =20
       =
BusinessComponents.LogToFile.Instance.logALineToFile(ex.ToString(),true);=
    =20
      }//try/catch
      return this.myConnection;
     }//get =20
  }//property myConnection
 =20
 =20
 =20