16.7.2.6 IsDBNull
IsDBNull methods indicate whether or not the specified attribute being retrieved is NULL.
                  
Overload List:
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                        IsDBNull(OracleConnection, IntPtr, string) This method indicates whether or not the attribute being retrieved, specified by OracleConnection, pointer, and attribute name, isNULL.
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                        IsDBNull(OracleConnection, IntPtr, int) This method indicates whether or not the attribute being retrieved, specified by OracleConnection, pointer, and attribute index, isNULL.