优胜美地更新后抛出编程错误

Question

昨天，该软件很好，升级到Yosemite OS后，只要查询数据库就会抛出异常。我查看了数据库表，数据仍然完好无损。什么似乎是错的？

ProgrammingError at /admin/user/employer/
column user_employer.id does not exist
LINE 1: SELECT "user_employer"."id", "user_employer"."created_at", "...
               ^
Request Method: GET
Request URL:    http://127.0.0.1:8000/admin/user/employer/
Django Version: 1.8.1
Exception Type: ProgrammingError
Exception Value:    
column user_employer.id does not exist
LINE 1: SELECT "user_employer"."id", "user_employer"."created_at", "...
               ^
Exception Location: /Users/charlesjavelona/.virtualenvs/student_job/lib/python3.4/site-packages/django/db/backends/utils.py in execute, line 64
Python Executable:  /Users/charlesjavelona/.virtualenvs/student_job/bin/python
Python Version: 3.4.0
Python Path:    
['/Users/charlesjavelona/Desktop/student_job/student_job',
 '/Users/charlesjavelona/.virtualenvs/student_job/lib/python34.zip',
 '/Users/charlesjavelona/.virtualenvs/student_job/lib/python3.4',
 '/Users/charlesjavelona/.virtualenvs/student_job/lib/python3.4/plat-darwin',
 '/Users/charlesjavelona/.virtualenvs/student_job/lib/python3.4/lib-dynload',
 '/Library/Frameworks/Python.framework/Versions/3.4/lib/python3.4',
 '/Library/Frameworks/Python.framework/Versions/3.4/lib/python3.4/plat-darwin',
 '/Users/charlesjavelona/.virtualenvs/student_job/lib/python3.4/site-packages']