我越来越:
ORA-00918:列的含义不明确的00918。00000-“列的含义不明确的”
每当我尝试运行时:
select first_name as student_first_name, last_name as student_last_name from super_student ss inner join sub_distance_learning sdl on sdl.student_id = ss.id inner join sub_academic_tutor sat on sat.id = sdl.academic_tutor_id inner join super_sub_lecturer ssl on ssl.id = sat.lecturer_id inner join super_employee se on se.id = ssl.employee_id;
该错误仅在包括以下内容时显示:
inner join super_employee se on se.id = ssl.employee_id;
有任何想法吗?
显然,不止一个表具有first_name和/或last_name其中,可能是super_student和super_employee。
first_name
last_name
super_student
super_employee
使用您很好定义的表别名:
select ss.first_name as student_first_name, ss.last_name as student_last_name