import time, resource
from sqlalchemy import *
from sqlalchemy.orm import *
from sqlalchemy.test.util import gc_collect
from sqlalchemy.test import profiling
db = create_engine('sqlite://')
metadata = MetaData(db)
Person_table = Table('Person', metadata,
Column('id', Integer, primary_key=True),
Column('type', String(10)),
Column('name', String(40)),
Column('sex', Integer),
Column('age', Integer))
Employee_table = Table('Employee', metadata,
Column('id', Integer, ForeignKey('Person.id'), primary_key=True),
Column('foo', String(40)),
Column('bar', Integer),
Column('bat', Integer))
class RawPerson(object): pass
class Person(object): pass
mapper(Person, Person_table)
class JoinedPerson(object):pass
class Employee(JoinedPerson):pass
mapper(JoinedPerson, Person_table, \
polymorphic_on=Person_table.c.type, polymorphic_identity='person')
mapper(Employee, Employee_table, \
inherits=JoinedPerson, polymorphic_identity='employee')
compile_mappers()
def setup():
metadata.create_all()
i = Person_table.insert()
data = [{'name':'John Doe','sex':1,'age':35, 'type':'employee'}] * 100
for j in xrange(500):
i.execute(data)
# note we arent fetching from employee_table,
# so we can leave it empty even though its "incorrect"
#i = Employee_table.insert()
#data = [{'foo':'foo', 'bar':'bar':'bat':'bat'}] * 100
#for j in xrange(500):
# i.execute(data)
print "Inserted 50,000 rows"
def sqlite_select(entity_cls):
conn = db.connect().connection
cr = conn.cursor()
cr.execute("SELECT id, name, sex, age FROM Person")
people = []
for row in cr.fetchall():
person = entity_cls()
person.id = row[0]
person.name = row[1]
person.sex = row[2]
person.age = row[3]
people.append(person)
cr.close()
conn.close()
def sql_select(entity_cls):
people = []
for row in Person_table.select().execute().fetchall():
person = entity_cls()
person.id = row['id']
person.name = row['name']
person.sex = row['sex']
person.age = row['age']
people.append(person)
#@profiling.profiled(report=True, always=True)
def orm_select():
session = create_session()
people = session.query(Person).all()
#@profiling.profiled(report=True, always=True)
def joined_orm_select():
session = create_session()
people = session.query(JoinedPerson).all()
def all():
setup()
try:
t, t2 = 0, 0
def usage(label):
now = resource.getrusage(resource.RUSAGE_SELF)
print "%s: %0.3fs real, %0.3fs user, %0.3fs sys" % (
label, t2 - t,
now.ru_utime - usage.last.ru_utime,
now.ru_stime - usage.last.ru_stime)
usage.snap(now)
usage.snap = lambda stats=None: setattr(
usage, 'last', stats or resource.getrusage(resource.RUSAGE_SELF))
gc_collect()
usage.snap()
t = time.clock()
sqlite_select(RawPerson)
t2 = time.clock()
usage('sqlite select/native')
gc_collect()
usage.snap()
t = time.clock()
sqlite_select(Person)
t2 = time.clock()
usage('sqlite select/instrumented')
gc_collect()
usage.snap()
t = time.clock()
sql_select(RawPerson)
t2 = time.clock()
usage('sqlalchemy.sql select/native')
gc_collect()
usage.snap()
t = time.clock()
sql_select(Person)
t2 = time.clock()
usage('sqlalchemy.sql select/instrumented')
gc_collect()
usage.snap()
t = time.clock()
orm_select()
t2 = time.clock()
usage('sqlalchemy.orm fetch')
gc_collect()
usage.snap()
t = time.clock()
joined_orm_select()
t2 = time.clock()
usage('sqlalchemy.orm "joined" fetch')
finally:
metadata.drop_all()
if __name__ == '__main__':
all()
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