[Err] ORA-00955: name is already used by an existing object解决方法：union 连接两个select数据集合 ，给表起的别名不能一样版权声明：本文为qq_39099370原创文章，遵循CC 4.0 BY-SA版权协议，转载请附上原文出处链接和本声明。原文链接：https://blog.csdn.net/qq_39099370/article/details/79644401