[Answered ]-Django view code has weird behaviour

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1👍

✅

Devices.objects.filter(device_id=field.device_id).values() is ValuesQuerySet which is derived from QuerySet and both of then are unevaluated which means that is a query yet is not executed on database until you apply list or iterate on it.
When you use json.dumps you need data not query.

Apply following to see the types:

Devices.objects.filter(device_id=field.device_id).values().__class__

django.db.models.query.ValuesQuerySet

Devices.objects.filter(device_id=field.device_id).values().__class__.__base__

django.db.models.query.QuerySet

👤Serjik

1👍

values() doesn’t return a simple data type.

I tried with a django model:

dir(myModel.objects.all().values())

[‘and‘, ‘bool‘, ‘class‘, ‘deepcopy‘, ‘delattr‘, ‘dict‘, ‘doc‘, ‘format‘, ‘getattribute‘, ‘getitem‘, ‘getstate‘, ‘hash‘, ‘init‘, ‘iter‘, ‘len‘, ‘module‘, ‘new‘, ‘nonzero‘, ‘or‘, ‘reduce‘, ‘reduce_ex‘, ‘repr‘, ‘setattr‘, ‘setstate‘, ‘sizeof‘, ‘str‘, ‘subclasshook‘, ‘weakref‘, ‘_add_hints’, ‘_as_sql’, ‘_base_queryset_class’, ‘_batched_insert’, ‘_clone’, ‘_create_object_from_params’, ‘_db’, ‘_earliest_or_latest’, ‘_extract_model_params’, ‘_fetch_all’, ‘_fields’, ‘_filter_or_exclude’, ‘_for_write’, ‘_has_filters’, ‘_hints’, ‘_insert’, ‘_known_related_objects’, ‘_merge_known_related_objects’, ‘_merge_sanity_check’, ‘_next_is_sticky’, ‘_populate_pk_values’, ‘_prefetch_done’, ‘_prefetch_related_lookups’, ‘_prefetch_related_objects’, ‘_prepare’, ‘_raw_delete’, ‘_result_cache’, ‘_setup_aggregate_query’, ‘_setup_query’, ‘_specialized_queryset_class’, ‘_sticky_filter’, ‘_update’, ‘aggregate’, ‘all’, ‘annotate’, ‘annotation_names’, ‘as_manager’, ‘bulk_create’, ‘complex_filter’, ‘count’, ‘create’, ‘dates’, ‘datetimes’, ‘db’, ‘defer’, ‘delete’, ‘distinct’, ‘earliest’, ‘exclude’, ‘exists’, ‘extra’, ‘extra_names’, ‘field_names’, ‘filter’, ‘first’, ‘get’, ‘get_or_create’, ‘in_bulk’, ‘is_compatible_query_object_type’, ‘iterator’, ‘last’, ‘latest’, ‘model’, ‘none’, ‘only’, ‘order_by’, ‘ordered’, ‘prefetch_related’, ‘query’, ‘raw’, ‘reverse’, ‘select_for_update’, ‘select_related’, ‘update’, ‘update_or_create’, ‘using’, ‘value_annotation’, ‘values’, ‘values_list’]

And this is the dir for a python array:

dir([])

[‘add‘, ‘class‘, ‘contains‘, ‘delattr‘, ‘delitem‘, ‘delslice‘, ‘doc‘, ‘eq‘, ‘format‘, ‘ge‘, ‘getattribute‘, ‘getitem‘, ‘getslice‘, ‘gt‘, ‘hash‘, ‘iadd‘, ‘imul‘, ‘init‘, ‘iter‘, ‘le‘, ‘len‘, ‘lt‘, ‘mul‘, ‘ne‘, ‘new‘, ‘reduce‘, ‘reduce_ex‘, ‘repr‘, ‘reversed‘, ‘rmul‘, ‘setattr‘, ‘setitem‘, ‘setslice‘, ‘sizeof‘, ‘str‘, ‘subclasshook‘, ‘append’, ‘count’, ‘extend’, ‘index’, ‘insert’, ‘pop’, ‘remove’, ‘reverse’, ‘sort’]

👤Admdebian

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