SQL Alchemy - connect, inserts and queries
Python and SQL databases example from a Well House Consultants training course
More on Python and SQL databases [link]
Source code: alch002 Module: Y113
# cd SQLAlchemy-1.0.8/
# sudo python setup.py install
# connect to the engine
from sqlalchemy import create_engine
# engine = create_engine('sqlite:///:memory:', echo=True)
engine = create_engine('sqlite:///:memory:')
from sqlalchemy.ext.declarative import declarative_base
Base = declarative_base()
# create a table
from sqlalchemy import Column, Integer, String
__tablename__ = 'users'
id = Column(Integer, primary_key=True)
name = Column(String)
fullname = Column(String)
password = Column(String)
return "<User(name='%s', fullname='%s', password='%s')>" % (
self.name, self.fullname, self.password)
print (User.__table__ )
# create a session
from sqlalchemy.orm import sessionmaker
Session = sessionmaker(bind=engine)
session = Session()
ed_user = User(name='ed', fullname='Ed Jones', password='edspassword')
our_user = session.query(User).filter_by(name='ed').first()
User(name='wendy', fullname='Wendy Williams', password='foobar'),
User(name='mary', fullname='Mary Contrary', password='xxg527'),
User(name='fred', fullname='Fred Flinstone', password='blah')])
# local changes and monitor they haven't been flushed
ed_user.password = 'f8s7ccs'
# Commit the changes
print ("1. -----------------------")
print ("2. -----------------------")
ed_user.name = 'Edwardo'
fake_user = User(name='fakeuser', fullname='Invalid', password='12345')
print (session.query(User).filter(User.name.in_(['ed', 'fakeuser'])).all())
print "1. ======================================"
for instance in session.query(User).order_by(User.id):
print (instance.name, instance.fullname)
for row in session.query(User, User.name).all():
print (row.User, row.name)
print "2. ======================================"
for u in session.query(User).order_by(User.id)[1:3]:
print "3. ======================================"
for user in session.query(User).\
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