Be aware that when using ADO.NET with Oracle .NET providers that the original, partially managed, provider and the current, fully managed provider behave differently in some scenarios. If your ADO.NET applications behave differently when switching between these Oracle providers, carefully check that you have the providers configured appropriately.
When using Oracle's ODBC driver, array fetches and some scrolling fetches might produce inconsistent behavior if you change the array size between fetches. To overcome this, build your application with SQL(NORESULTARRAY). When this is set, OpenESQL performs single row fetches under the covers, bypassing this limitation.