sqlalchemy PostgreSQLInheritance

sqlalchemy_pg_inherits.py

# encoding=utf8

'''
https://bitbucket.org/zzzeek/sqlalchemy/wiki/UsageRecipes/PostgreSQLInheritance
'''
from sqlalchemy import create_engine
from sqlalchemy.ext.declarative import as_declarative, declared_attr
from sqlalchemy.orm import scoped_session, sessionmaker

engine = create_engine('postgresql:///test', convert_unicode=True, echo=False)
Session = sessionmaker(autocommit=False,
                       autoflush=False,
                       bind=engine)
session = scoped_session(Session)


from sqlalchemy import Column, Integer, TIMESTAMP, func, String
from sqlalchemy import event


@as_declarative()
class Base(object):
    @declared_attr
    def __tablename__(cls):
        return cls.__name__.lower() + 's'

    id = Column(Integer, primary_key=True)
    created_date = Column(TIMESTAMP, nullable=False, server_default=func.current_timestamp())
    updated_date = Column(TIMESTAMP, nullable=False, server_default=func.current_timestamp(),
                          onupdate=func.current_timestamp())


class T1(Base):
    __tablename__ = 't1'
    name = Column(String(20), nullable=False)
    age = Column(Integer, nullable=False)


@event.listens_for(T1.__table__, 'after_create')
def create_child_tables(target, connection, **kw):
    print(target, kw)
    connection.execute("""
        create table  t2 (
            flag boolean default false
        ) inherits(t1)
    """)


Base.metadata.create_all(bind=engine)