Sqlalchemy: Alembic Bulk Insert Fails: 'str' Object Has No Attribute '_autoincrement_column'

My model looks like class Category(UserMixin, db.Model): __tablename__ = 'categories' uuid = Column('uuid', GUID(), default=uuid.uuid4, primary_key=True,

Solution 1:

all I had to do is to create a table before bulk_insert, even if I have a explicit schema in separate models.py

import sqlalchemy as sa
from sqlalchemy.sql import table
from alembic import op

def upgrade():
     categories = table('categories',
                       sa.Column('uuid', UUID(),
                              primary_key=True,
                              unique=True, autoincrement=False),
                       sa.Column('name', String),
                       sa.Column('parent', String),
                       sa.Column('created_on', sa.types.DateTime(timezone=True),
                              default=datetime.utcnow())
    )
    op.bulk_insert(categories,
                   [
                       {'name': 'first', 'parent': 'first_parent'},
                       {'name': 'second', 'parent': 'second_parent'}
                   ]
    )

and then I was able to to run alembic upgrade head without any issues and data was serialized successfully in database.