Pylons, SQlite and autoincrementing fields
Hey! Just started working with Pylons in conjunction with SQLAlchemy, and my model looks something like this:
from sqlalchemy import Column
from sqlalchemy.types import Integer, String
from helloworld.model.meta i开发者_开发技巧mport Base
class Person(Base):
__tablename__ = "person"
id = Column(Integer, primary_key=True)
name = Column(String(100))
email = Column(String(100))
def __init__(self, name='', email=''):
self.name = name
self.email = email
def __repr__(self):
return "<Person('%s')" % self.name
To avoid sqlite reusing id's that might have been deleted, I want to add AUTOINCREMENT to the column "id". I've looked through the documentation for sqlalchemy and saw that the sqlite_autoincrement can be issued. An example where this attribute is given can be found here.
sqlite_autoincrement seems though to be issued when creating the table itself, and I just wondered how it can be supplied when using a declarative style of the model such as mine.
Try including a __table_args__
attribute with the arguments you would pass to Table
constructors in the traditional (non-declarative) data definition style, e.g.:
class Person(Base):
__tablename__ = "person"
__table_args__ = {'sqlite_autoincrement': True}
If you have to include several arguments, use this form instead (dict has to be last):
__table_args__ = (
Unique('foo'),
# ...
{'sqlite_autoincrement': True}
)
From the Table configuration section of the Declarative SQLAlchemy documentation:
Table arguments other than the name, metadata, and mapped
Column
arguments are specified using the__table_args__
class attribute. This attribute accommodates both positional as well as keyword arguments that are normally sent to theTable
constructor.
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