I am writing a C# program that uses MySQL as database and MySQL ODBC
3.51 driver.

It works fine all the way except this scenario that needs to be
addressed.

1. Get a set of records to process (this brings back a datatable in C#
and works fine. It uses a limit of 30 records each time).
2. Process the information from Step 1.
3. Check in table B if data of this exists in table B
4. Based on info from Step 3 Insert/Update data in table B (in either
case only one row will be affected)
5. Get next record in Step 2 and repeat further till all records
processed.


Doing so throws exception that I have no idea.
>From Event Viewer.
First I get two COM+ errors and then my application log.

COM+ errors category - unknown and Event - 4786:
------------------------------------------------------------ ------------------------------------------------------------ ------------------------
The system has called a custom component and that component has failed
and generated an exception. This indicates a problem with the custom
component. Notify the developer of this component that a failure has
occurred and provide them with the information below.
Component Prog ID: 0[ODBC][Env 32212a0]
Method Name: IDispenserDriver::DestroyResource
Process Name: MyApp.exe
Exception: C0000005
Address: 0x7C910E03
Call Stack:
ntdll!wcsncpy + 0x374
myodbc3! + 0x4DB5D
myodbc3!SQLTransact + 0x8F5D

COM+ Second error:
------------------------------------------------------------ ------------------------------------------------------------ ------------------------

The system has called a custom component and that component has failed
and generated an exception. This indicates a problem with the custom
component. Notify the developer of this component that a failure has
occurred and provide them with the information below.
Component Prog ID: 0[ODBC][Env 32212a0]
Method Name: IDispenserDriver::CreateResource
Process Name: MyApp.exe
Exception: C0000005
Address: 0x7C91142E
Call Stack:
ntdll!wcsncpy + 0x99F
myodbc3! + 0x4DAA2
myodbc3! + 0x4DAC4

Then my app logs:
------------------------------------------------------------ ------------------------------------------------------------ ------------------------
ERROR - no error information available
at System.Data.Odbc.OdbcConnection.Open()
..... <remaining stack trace of my app 2 items>


Second log from my app:
------------------------------------------------------------ ------------------------------------------------------------ ------------------------

System.Data
Object reference not set to an instance of an object.
at System.Data.Common.Odbc32.SQLDisconnect(HandleRef
ConnectionHandle)
at System.Data.Odbc.DBCWrapper.CloseAndRelease()
at System.Data.Odbc.OdbcConnection.DisposeClose()
at System.Data.Odbc.OdbcConnection.Close()
at System.Data.Odbc.OdbcConnection.Dispose(Boolean disposing)
at System.ComponentModel.Component.Dispose()
..... <remaining stack trace of my app 2 items>

<END OF LOGS>


What is going on? How do I resolve this?

Thanks in advance.

PS: I may cross post this in different forums (possible other forums:
MySQL, C#)

I switched to .net connector and it works well now.



zb wrote:
> I am writing a C# program that uses MySQL as database and MySQL ODBC
> 3.51 driver.
>
> It works fine all the way except this scenario that needs to be
> addressed.
>
> 1. Get a set of records to process (this brings back a datatable in C#
> and works fine. It uses a limit of 30 records each time).
> 2. Process the information from Step 1.
> 3. Check in table B if data of this exists in table B
> 4. Based on info from Step 3 Insert/Update data in table B (in either
> case only one row will be affected)
> 5. Get next record in Step 2 and repeat further till all records
> processed.
>
>
> Doing so throws exception that I have no idea.
> >From Event Viewer.
> First I get two COM+ errors and then my application log.
>
> COM+ errors category - unknown and Event - 4786:
> ------------------------------------------------------------ ------------------------------------------------------------ ------------------------
> The system has called a custom component and that component has failed
> and generated an exception. This indicates a problem with the custom
> component. Notify the developer of this component that a failure has
> occurred and provide them with the information below.
> Component Prog ID: 0[ODBC][Env 32212a0]
> Method Name: IDispenserDriver::DestroyResource
> Process Name: MyApp.exe
> Exception: C0000005
> Address: 0x7C910E03
> Call Stack:
> ntdll!wcsncpy + 0x374
> myodbc3! + 0x4DB5D
> myodbc3!SQLTransact + 0x8F5D
>
> COM+ Second error:
> ------------------------------------------------------------ ------------------------------------------------------------ ------------------------
>
> The system has called a custom component and that component has failed
> and generated an exception. This indicates a problem with the custom
> component. Notify the developer of this component that a failure has
> occurred and provide them with the information below.
> Component Prog ID: 0[ODBC][Env 32212a0]
> Method Name: IDispenserDriver::CreateResource
> Process Name: MyApp.exe
> Exception: C0000005
> Address: 0x7C91142E
> Call Stack:
> ntdll!wcsncpy + 0x99F
> myodbc3! + 0x4DAA2
> myodbc3! + 0x4DAC4
>
> Then my app logs:
> ------------------------------------------------------------ ------------------------------------------------------------ ------------------------
> ERROR - no error information available
> at System.Data.Odbc.OdbcConnection.Open()
> .... <remaining stack trace of my app 2 items>
>
>
> Second log from my app:
> ------------------------------------------------------------ ------------------------------------------------------------ ------------------------
>
> System.Data
> Object reference not set to an instance of an object.
> at System.Data.Common.Odbc32.SQLDisconnect(HandleRef
> ConnectionHandle)
> at System.Data.Odbc.DBCWrapper.CloseAndRelease()
> at System.Data.Odbc.OdbcConnection.DisposeClose()
> at System.Data.Odbc.OdbcConnection.Close()
> at System.Data.Odbc.OdbcConnection.Dispose(Boolean disposing)
> at System.ComponentModel.Component.Dispose()
> .... <remaining stack trace of my app 2 items>
>
> <END OF LOGS>
>
>
> What is going on? How do I resolve this?
>
> Thanks in advance.
>
> PS: I may cross post this in different forums (possible other forums:
> MySQL, C#)