Hello,
I started to write my PostgreSQL layer. I tried pyPgSQL and PyGreSQL. I
made a *very minimal* performance test and comparsion with the same
thing in php. Table "movie" has 129 record and many fields.
I found PyGreSQL / DB-API / fetchall horrible slow (32 sec in my test).
PHP did 13 secs and it gave the result in associative array. Maybe I did
something bad.
pyPgSQL / DB-API raised a futurewarning and didn't worked.
pyPgSQL / libpg worked well. I can create php-like dictionary result in
14 secs.
Here is the code. It's only a test...
Mage
------ test.py --------
import mpypg
import datetime
print 'This is a python postgesql module'
db = mpypg.mpypgdb('dbname=test host=localhost')
def test():
res = db.query('select * from movie')
#print res['fields']
#print res['rows']
#pass
def test2():
res = db.query('select * from movie')
#print res['fields']
#print len(res['rows'])
#print res['rows']
print len(res)
print res[1]
start = datetime.datetime.now()
for i in range(100):
test()
#pass
end = datetime.datetime.now()
print end - start
test2()
------ mpypg.py --------
from pyPgSQL import libpq
from pyPgSQL import PgSQL
import sys
import pgdb
mpypg_connect_error_message = 'Could not connect to the database'
mpypg_query_error_message = 'Could not run the query'
class mpypgdb:
'my database class'
def __init__(self,str):
try:
self.database = libpq.PQconnectdb(str)
except:
mpypg_error_msg(mpypg_connect_error_message)
def query(self,query):
try:
res = self.database.query(query)
fields = tuple([res.fname(i) for i in range(res.nfields)])
rows = []
'''
for name in fields:
rows[name] = []
for i in range(res.ntuples):
for j in range(len(fields)):
rows[fields[j]].append(res.getvalue(i,j))
'''
'''
for j in range(len(fields)):
rows[fields[j]] = tuple([res.getvalue(i,j) for i in
range(res.ntuples)])
'''
for i in range(res.ntuples):
rows.append(dict([(fields[j], res.getvalue(i,j)) for j
in range(len(fields))]))
res.clear()
result = {'fields': fields, 'rows': rows}
return result;
except:
mpypg_error_msg(mpypg_query_error_message)
class mpgdb:
'my database class'
def __init__(self,str):
try:
self.database = pgdb.connect(database='test')
except:
mpypg_error_msg(mpypg_connect_error_message)
def query(self,query):
try:
cursor = self.database.cursor()
res = cursor.execute(query)
#result = {'fields': fields, 'rows': cursor.fetchall()}
result = [cursor.fetchone() for i in range(cursor.rowcount)]
#result = cursor.fetchall()
return result;
except:
mpypg_error_msg(mpypg_query_error_message)
def mpypg_error_msg(message):
'Database error handler'
sys.exit(message)
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