So you can very easily run a raw SQL statement to set the value to anything you like. CreatureDataMixin.dataclassparams DataclassParams (initTrue,reprTrue,eqTrue,orderFalse,unsafehashFalse,frozenTrue) I'll have to look into that. This allows you to use the enums in your code, which is very handy since most code editors will autocomplete the set of possible names.īe aware though, that this "enum-ness" is enforced by SQLAlchemy and not at the database level. It would be possible to have Enum check to see if the data type is a dataclass, and then see if the repr is set to be automatically created. Message_type = db.Column(IntEnum(MessageTypes), default=MessageTypes.text) Now that this new column type is available, here's how it looks in the model definition. ![]() Super(IntEnum, self)._init_(*args, **kwargs)ĭef process_bind_param(self, value, dialect):ĭef process_result_value(self, value, dialect): The default would have stored the enum's *name* (ie the string).ĭef _init_(self, enumtype, *args, **kwargs): In order to do so using SQLAlchemy, we have to define a special column type which will automatically store/return the enum's value.Įnables passing in a Python enum and storing the enum's *value* in the db. I prefer to store the enum's values (eg 1 in the example above) rather than its name (eg "text" in the example above). Python enums are special beasts which are essentially key-value stores, ie each enum has both a name and a value attribute.Īs you can see, the comparator for an enum uses its value. You may also be interested in reading about enums from the author of SQLAlchemy, although this article was written in 2011 and may be dated. ![]() Note that I'm not talking about enums at the database level - these are definitely useful but perhaps not as flexible as just defining enums in your model definition (ie changing the former requires a database migration, but the latter only requires a code / definition change). The http module also defines the following enums that. Python doesnt have an explicit enum type, but enums in most languages are just a way for us to refer to closely-related items in a human-readable way. okies has utilities for implementing state management with cookies. rver contains basic HTTP server classes based on socketserver. This article will show you how to use enums in Python with SQLAlchemy models. http.client is a low-level HTTP protocol client for high-level URL opening use urllib.request. ![]() Of course, it's not suited for columns with high cardinality (ie lots of different values) - but if you are only expecting a small set of values AND you are annoyed at values being stored as 'green' vs 'Green' vs 'Grreen' every time an engineer mistypes something, there's lots of reasons to like enums. enum, stands for an enumeration it is an symbolic representation of set of constants mapped against bound to unique names. so maintains the normal Enum invariants (such as not being comparable to other enumerations): Here is a python example that shows how to use the IntEnum. I'm a big fan of using enums, as they generally force all values appearing in a database column to be in a consistent format.
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