인프런 커뮤니티 질문&답변

mysql 에 테이블을 기존에 만들어 둔게 있습니다.

다른 서비스가 데이터를 쌓아 놓는 테이블인데 여기를 ORM으로 조회를 한번 해보고 싶습니다.

로그성 테이블이라 pk가 없습니다.

python manage.py inspectdb 로 모델 코드를 만들어 내긴 했습니다.

python shell로 조회를 하려고 하는데 id 필드를 찾으려는 시도를 계속 합니다.

기존에 만들어진 DB 스키마를 ORM으로 사용려고 만든 것이 inspectdb 일것 같은데

장고 ORM 구조가 PK를 필수로 가져야 하는 구조인지 궁금합니다.

(구글링 해보면 PK가 필수라는 이야기도 있고, CHATGPT에게 물어보면 Meta클래스에 managed가 False이면 괜찮다는 답변이 나오네요)

inspectdb로 만들어진 코드에는 Meta 클래스가 아래와 같이 있습니다.

class MacLog(models.Model):
    timestamp = models.DateTimeField()
    sw_ip = models.CharField(max_length=20)
    mac = models.CharField(max_length=255)
    port = models.CharField(max_length=20)

    class Meta:
        managed = False
        db_table = 'mac_log'

다음은 에러가 나는 내용 입니다.

>>> from django.db.models import QuerySet
>>> from maccol.models import MacLog
>>> 
>>> qs = QuerySet(MacLog)
>>> for item in qs:
...     print(item)
... 

  None
Execution time: 0.019902s [Database: default]
Traceback (most recent call last):
  File "/Users/dcu/workspace/maccol/venv/lib/python3.11/site-packages/django/db/backends/utils.py", line 89, in _execute
    return self.cursor.execute(sql, params)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/dcu/workspace/maccol/venv/lib/python3.11/site-packages/django/db/backends/mysql/base.py", line 75, in execute
    return self.cursor.execute(query, args)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/dcu/workspace/maccol/venv/lib/python3.11/site-packages/MySQLdb/cursors.py", line 179, in execute
    res = self._query(mogrified_query)
          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/dcu/workspace/maccol/venv/lib/python3.11/site-packages/MySQLdb/cursors.py", line 330, in _query
    db.query(q)
  File "/Users/dcu/workspace/maccol/venv/lib/python3.11/site-packages/MySQLdb/connections.py", line 261, in query
    _mysql.connection.query(self, query)
MySQLdb.OperationalError: (1054, "Unknown column 'mac_log.id' in 'field list'")

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "<console>", line 1, in <module>
  File "/Users/dcu/workspace/maccol/venv/lib/python3.11/site-packages/django/db/models/query.py", line 398, in __iter__
    self._fetch_all()
  File "/Users/dcu/workspace/maccol/venv/lib/python3.11/site-packages/django/db/models/query.py", line 1881, in _fetch_all
    self._result_cache = list(self._iterable_class(self))
                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/dcu/workspace/maccol/venv/lib/python3.11/site-packages/django/db/models/query.py", line 91, in __iter__
    results = compiler.execute_sql(
              ^^^^^^^^^^^^^^^^^^^^^
  File "/Users/dcu/workspace/maccol/venv/lib/python3.11/site-packages/django/db/models/sql/compiler.py", line 1562, in execute_sql
    cursor.execute(sql, params)
  File "/Users/dcu/workspace/maccol/venv/lib/python3.11/site-packages/django_extensions/management/debug_cursor.py", line 49, in execute
    return utils.CursorWrapper.execute(self, sql, params)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/dcu/workspace/maccol/venv/lib/python3.11/site-packages/django/db/backends/utils.py", line 67, in execute
    return self._execute_with_wrappers(
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/dcu/workspace/maccol/venv/lib/python3.11/site-packages/django/db/backends/utils.py", line 80, in _execute_with_wrappers
    return executor(sql, params, many, context)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/dcu/workspace/maccol/venv/lib/python3.11/site-packages/django/db/backends/utils.py", line 84, in _execute
    with self.db.wrap_database_errors:
  File "/Users/dcu/workspace/maccol/venv/lib/python3.11/site-packages/django/db/utils.py", line 91, in __exit__
    raise dj_exc_value.with_traceback(traceback) from exc_value
  File "/Users/dcu/workspace/maccol/venv/lib/python3.11/site-packages/django/db/backends/utils.py", line 89, in _execute
    return self.cursor.execute(sql, params)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/dcu/workspace/maccol/venv/lib/python3.11/site-packages/django/db/backends/mysql/base.py", line 75, in execute
    return self.cursor.execute(query, args)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/dcu/workspace/maccol/venv/lib/python3.11/site-packages/MySQLdb/cursors.py", line 179, in execute
    res = self._query(mogrified_query)
          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/dcu/workspace/maccol/venv/lib/python3.11/site-packages/MySQLdb/cursors.py", line 330, in _query
    db.query(q)
  File "/Users/dcu/workspace/maccol/venv/lib/python3.11/site-packages/MySQLdb/connections.py", line 261, in query
    _mysql.connection.query(self, query)
django.db.utils.OperationalError: (1054, "Unknown column 'mac_log.id' in 'field list'")