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I've been using an array of enums with postgres and SQLAlchemy successfully over the past year like so:

class MyModel(BaseModel):
    enum_field = Column(postgresql.ARRAY(EnumField(MyEnum, native_enum=False)))

The EnumField is from the sqlalchemy_enum34 library, a small wrapper around the builtin enum that uses Python enums as Python representation instead of strings.

Although the docs say, array of enum is not supported, I guess it worked, because I chose 'native_enum=False'. Recently I noticed that it doesn't work anymore, I think it's due to the upgrade from SQLA 1.0 to 1.1, but I'm not sure.

The problem is, that it generates invalid DQL:

CREATE TABLE my_model (
    enum_field VARCHAR(5)[3] NOT NULL CHECK (contexts IN ('ONE', 'TWO', 'THREE'))
)

The error I get is:

ERROR:  malformed array literal: "ONE"
DETAIL:  Array value must start with "{" or dimension information.

Any idea how I can get back my enum array?
By the way: when it worked, no CHECK constraint was actually created, just an array of varying. I'm ok with that as long as I can use enums in my Python code (e.g. query.filter(enum_field==MyEnum.ONE))

Answers

Mike Bayer answered on the sqlalchemy mailing list:

you probably want to add create_constraint=False, see if that works

http://docs.sqlalchemy.org/en/latest/core/type_basics.html?highlight=enum#sqlalchemy.types.Enum.params.create_constraint

I can now create the table (without any CHECK).