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Python
Yuuki TakahashiYuuki Takahashi

Djangoのすべてのモデルとフィールドを走査して、利用している最大のIDカラムとあとどのくらい採番可能かチェックするスクリプト

def describe_remaining_id_length():
    import django.apps
    from django.db.models import AutoField, BigAutoField, SmallAutoField
    results = []
    print('Iterate all Models', end="")
    for model in django.apps.apps.get_models():
        model_name = model.__name__
        for field in model._meta.get_fields():
            if isinstance(field, AutoField):
                field_name = field.name
                try:
                    latest_model = model.objects.latest(field_name)
                    latest_id = getattr(latest_model, field_name)
                except model.DoesNotExist:
                    latest_id = 0

                if isinstance(field, BigAutoField):
                    int_max = 9_223_372_036_854_775_807
                elif isinstance(field, SmallAutoField):
                    int_max = 32_767
                else:
                    int_max = 2_147_483_647

                field_type_name = type(field).__name__
                remaining = int_max - latest_id

                results.append({
                    'model_name': model_name,
                    'field_name': field_name,
                    'field_name_type': field_type_name,
                    'latest_id': latest_id,
                    'remaining': remaining,
                })
                print(".", end="")
    print('')
    print('')
    results = sorted(results, key=lambda x: x['remaining'])

    print('model_name,field_name,field_name_type,latest_id,remaining')
    for result in results:
        print(f"{result['model_name']},{result['field_name']},{result['field_name_type']},{result['latest_id']},{result['remaining']}")