Re: [SQLObject] Temporary databases / Closing the :memory: database connection

[Oleg B. <ph...@ph...>]

Hi!

On Thu, Oct 17, 2013 at 10:01:53PM +0100, "Maciej (Matchek) Blizi??ski" <ma...@op...> wrote:
> import sqlobject
> 
> class Foo(sqlobject.SQLObject):
>   bar = sqlobject.UnicodeCol(length=250, unique=True)
> 
> db_uri = 'sqlite:/:memory:?cache=false'
> while True:
>   sqlobject.sqlhub.processConnection = sqlobject.connectionForURI(db_uri)
>   Foo.createTable()
>   sqlobject.sqlhub.processConnection.close()
>   sqlobject.sqlhub.processConnection = None
>   sqlobject.dbconnection.TheURIOpener.cachedURIs = {}
> 
> The process' memory kept growing. It started at around 30MB and was
> steadily raising up to 300MB at which point I stopped the process. I
> didn't do any more digging yet.

   The program eats my memory very quickly and fails with MemoryError in
a few seconds.

On Sat, Oct 19, 2013 at 11:44:03AM +0100, "Maciej (Matchek) Blizi??ski" <ma...@op...> wrote:
> On Fri, Oct 18, 2013 at 01:14:46AM +0400, Oleg Broytman wrote:
> >    It would be interesting to test if the problem lies in SQLite,
> > PySQLite or SQLObject.
> 
> Looks like it's not SQLite, the following runs with stable memory use at
> about 7MB, I ran it for about an hour:
> 
> import sqlite3
> while True:
>   conn = sqlite3.connect(":memory:")
>   c = conn.cursor()
>   c.execute('CREATE TABLE foo (bar TEXT);')
>   conn.commit()
>   conn.close()

   This one works for me, eats 9M at the start but doesn't grow.

   And this one also works perfectly:

import sqlobject

class Foo(sqlobject.SQLObject):
  bar = sqlobject.UnicodeCol(length=250, unique=True)

db_uri = "sqlite:/:memory:"
while True:
  Foo.setConnection(db_uri)
  Foo.createTable()
  Foo._connection.close()

   It takes 15M at startup but doesn't grow.

   Very puzzling!

Oleg.
-- 
     Oleg Broytman            http://phdru.name/            ph...@ph...
           Programmers don't die, they just GOSUB without RETURN.