Very Computer

So here's the deal -

I'm a novice at using ADO, (not to mention database usage in general) and
have spent much nashing of teeth looking for the elusive C++ examples that
exist under rocks here and there in amongst the VB  and HTML examples.  I've
managed to piece together enough information to get most of what I want to
do done, however, my attempts at using the transaction functions have as of
yet been unsuccessful.

I'm runnning NT 4.0 service pack 4.
Developing with VC++ 6.0.
I have Access 97 installed (my database needs at this point are small...).
And to the best of my knowledge I have installed the lastest and greatest
rendition of ADO - or so the web download page implied.

When I try and use 'BeginTrans' - an exception is thrown and I'm able to
extract the following error:

     "Description = [Microsoft][ODBC Microsoft Access 97 Driver]Operation
invalid at this time ".

I've decided that either I have the wrong drivers, and they don't support
the requested behavior - (but I believe them to be the most recent
drivers...?)  OR I'm somehow using the method incorrectly (see code snipit
below).

Has anyone experienced this?  What obvious thing am I not seeing?

Any comments would be greatly appreciated!

Thanx,
Kevin Pumarlo

P.S
I'm using the VC++ extensions for ADO - most handy given the alternative...

        CActionTableRs          rsActionTable;
        HRESULT                         hRes;
        IADORecordBinding*      pIrbRs1 = NULL;

        // Trap any error/exception
    try
    {
            //------------------------
            // Open Connection Object
            //------------------------

            // Create Connection Object - Conn1
            Conn1.CreateInstance( __uuidof( Connection ) );
            Conn1->ConnectionString = bstrAccessConnect;
            Conn1->Open( bstrEmpty, bstrEmpty, bstrEmpty, -1 );

            //-----------------------------------
            // Open Parameterized Command Object
            //-----------------------------------

            // Create Command Object
            Cmd1.CreateInstance( __uuidof( Command ) );
            Cmd1->ActiveConnection = Conn1;

            // Open Recordset Object  - Rs1
            Rs1.CreateInstance( __uuidof( Recordset ) );
            Rs1->Open(_bstr_t(bstrTable),
_variant_t(Conn1.GetInterfacePtr()), adOpenKeyset,
                                  adLockOptimistic, adCmdTable);

            Conn1->BeginTrans();

**** !!!!  At this point a '_com_error' exception is thrown yielding the
afore mentioned description.

I'm not sure if this applies to ADO, but when using ODBC via CDatabase and
CRecordSet, the BeginTrans fails if there are any open connections to the
record set. To get a transaction to work, I had to create a new connection.

Brian

Quote:> So here's the deal -

> I'm a novice at using ADO, (not to mention database usage in general) and
> have spent much nashing of teeth looking for the elusive C++ examples that
> exist under rocks here and there in amongst the VB  and HTML examples.
I've
> managed to piece together enough information to get most of what I want to
> do done, however, my attempts at using the transaction functions have as
of
> yet been unsuccessful.

> I'm runnning NT 4.0 service pack 4.
> Developing with VC++ 6.0.
> I have Access 97 installed (my database needs at this point are small...).
> And to the best of my knowledge I have installed the lastest and greatest
> rendition of ADO - or so the web download page implied.

> When I try and use 'BeginTrans' - an exception is thrown and I'm able to
> extract the following error:

>      "Description = [Microsoft][ODBC Microsoft Access 97 Driver]Operation
> invalid at this time ".

> I've decided that either I have the wrong drivers, and they don't support
> the requested behavior - (but I believe them to be the most recent
> drivers...?)  OR I'm somehow using the method incorrectly (see code snipit
> below).

> Has anyone experienced this?  What obvious thing am I not seeing?

> Any comments would be greatly appreciated!

> Thanx,
> Kevin Pumarlo

> P.S
> I'm using the VC++ extensions for ADO - most handy given the
alternative...

> CActionTableRs rsActionTable;
> HRESULT hRes;
> IADORecordBinding* pIrbRs1 = NULL;

> // Trap any error/exception
>     try
>     {
>             file://------------------------
>             // Open Connection Object
>             file://------------------------

>             // Create Connection Object - Conn1
>             Conn1.CreateInstance( __uuidof( Connection ) );
>             Conn1->ConnectionString = bstrAccessConnect;
>             Conn1->Open( bstrEmpty, bstrEmpty, bstrEmpty, -1 );

>             file://-----------------------------------
>             // Open Parameterized Command Object
>             file://-----------------------------------

>             // Create Command Object
>             Cmd1.CreateInstance( __uuidof( Command ) );
>             Cmd1->ActiveConnection = Conn1;

>             // Open Recordset Object  - Rs1
>             Rs1.CreateInstance( __uuidof( Recordset ) );
>             Rs1->Open(_bstr_t(bstrTable),
> _variant_t(Conn1.GetInterfacePtr()), adOpenKeyset,
>       adLockOptimistic, adCmdTable);

>             Conn1->BeginTrans();

> **** !!!!  At this point a '_com_error' exception is thrown yielding the
> afore mentioned description.