TypeDefinition :: viewGroup - Get Group specifications
The function returns a string containing the GROUP BY expression as being defined in a view definition or SELECT statement. In case of errors or invalid type definition, the function throws an exception.
Implementation details
When the type definition is a valid view definition, the function returns a string containing the GROUP BY expression. The GROUP BY expression returned contains the maximum of information including data type definition and member names. In a user-defined definition or script this could be shortened.
When no GROUP BY clause been defined for the view, an empty string is returned.
When calling the function with an invalid type definition or when the type definition does not refer to an view type, the function throws an exception. In order to check, whether the data type is a view type, isView() might be called.