Unable to cast object of type 'System.DBNull' to type 'CoreLab.Oracle.OracleObject'

Unable to cast object of type 'System.DBNull' to type 'CoreLab.Oracle.OracleObject'

Postby kdulaney » Wed 26 Mar 2008 20:30

I am calling an Oracle Package that returns nested UDT's that conform to an XML schema. It seems to work fine for most data but I have run into an instance with certain data where I receive this error: Unable to cast object of type 'System.DBNull' to type 'CoreLab.Oracle.OracleObject'. Apparently there is a problem converting the returned UDT.

I can call the package using SQL+ and it executes successfully.

Is there any way to debug this to figure out why the OraDirect.Net package throws an error while SQL+ returns data?

Here is the code that makes the call:
Code: Select all
return (OracleObject)package.ExecuteProcedure(OracleFunctionName, col, true)
where col=collection of strongly-typed parameters.

I have downloaded the latest version of OraDirect.Net v4.50.31 - and am using .net framework 2.0.

Thanks[/code]
kdulaney
 
Posts: 2
Joined: Wed 26 Mar 2008 20:15

Postby Alexey.mdr » Thu 27 Mar 2008 16:00

Do you use OraDirect .NET “Oracle Package Wizard ”?
If yes, try setting on
-Use Nullable types- in “Choose method and parameter naming style” section of the wizard.

Otherwise, please send me (alexeyman*crlab*com) a small test project to reproduce the problem.
Alexey.mdr
 
Posts: 729
Joined: Thu 13 Dec 2007 10:24

Postby kdulaney » Wed 02 Apr 2008 20:04

After spending more time troubleshooting this, it looks like a size limitation on the object being returned. I can change the date range of the data that I am requesting and it gets the month that I thought was breaking. Basically, I can get all my data if I split into two separate calls (two date ranges) but if I combine the date ranges to one range/one call, it fails. That might explain why it works in SQL+ and SQLDeveloper but not in OraDirect. I will be searching the forums now for size limitations. If you know of a limitation, is there anyway to override it?

Thanks.
kdulaney
 
Posts: 2
Joined: Wed 26 Mar 2008 20:15

Postby Alexey.mdr » Thu 03 Apr 2008 14:59

Could you post the error and the stacktrace?
Also please send me or post here a block of code that can show the problem
(please include database objects script).
Alexey.mdr
 
Posts: 729
Joined: Thu 13 Dec 2007 10:24


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