On Aug 15, 2011, at 2:11 PM, Philip Thompson wrote:
On Mon, Aug 15, 2011 at 1:43 PM, LAMP <l...@afan.net> wrote:
Hi all,
This is THE question that bothers me for a while... I always was
keeping session info, like user ID, organization ID, selected book
ID... within $_SESSION array. Main reason is to access and maintain
it faster than keeping them inside session table. And, also, one
less mysql connection.
Though, in last project the $_SESSION grow up to around 30, even 50
elements of the array. And several people mentioned it's better to
keep so big session data in mysql than in $_SESSION.
My question is pros and cons $_SESSION vs. mysql session. And, if
the amount of data is only reason, when is better to keep all data
in $_SESSION and when to store them in mysql?
Thanks for any help,
LAMP
Hi all. Long time no see. I personally think 30-50 elements in an
array is not a lot of data (unless you're storing hundreds of megs
of data per element). You really have to weigh the pros and cons of
using file-based session storage versus database session storage.
With a quick google search, this article by Chris Shiftlett came up: http://shiflett.org/articles/storing-sessions-in-a-database
. Specially look at the background section. It goes over a couple
reasons to use a database. While this list is not exhaustive by any
means, it should get you thinking. If the biggest reason for wanting
to use a database over the file system is because of the space, then
you may want to reconsider....
In file-based session storage, the session data is saved in a
particular location (as specified in php.ini). So, if you have 10MB
of data, this will be will stored in a file slightly larger than
10MB because I believe the data is serialized in some form. This
file is accessed upon page load and is written to for the next page
request. File I/O is generally pretty fast... generally much faster
than database I/O.
In the database storage, you must run queries to pull the data
necessary. This requires a connection plus the time to query plus
the time to organize the data. If you have 10MB of data, then you
still have to pull all of that from the database, so I don't believe
you're getting any speed advantage. If you're application is running
on multiple servers, then you'd want to consider the database
storage. IMO, only use the database (for session storage) if it
solves a problem that can be easily fixed otherwise by using file-
based session storage.
Hope that helps,
~Philip
--
http://lonestarlightandsound.com/
I apologize for posting not-complete data :-)
The size of the data is, I believe, small. 1-2 words per array element
or number. No image or something like that is stored in $_SESSION. I
believe no more than few Kb.
My concern is not only speed, than handling (as you said "time to
query plus the time to organize the data..."),as well as security. I
read Shiflett's article but it dates from 2004 and I believe some
stuff are changed too :-)
As I said, I prefer working with $_SESSION instead storing data into
session table, but always wondered is that correct approach.
Thanks,
LAMP
