ORA-19239: XPTY0019 – It is a type error if the result of an step (other than the last step) in a path expression contains an atomic value
Cause: The step expression returned a sequence containing an atomic value.
Action: Fix the path expression to return only nodes.
ORA-19239: XPTY0019错误表明路径表达式中，除了最后一步之外，其他任何步骤的结果都不应该是原子值。