Moving database calls out of Session library into sessions model

[jtboofle]

For those of us with 'special' database needs (in my case, connecting to DB2 and using non-standard field names in the session table), having all the database calls embedded in the session class is a pain in the keister. I've moved them out into a sessions model which makes fiddling around with session handling a simple matter of overriding 5 function calls.

[gaker]

hrm, I see your point, however, would good support for DB2 be better? How are you working with DB2 now, is that something you'd like to see about contributing back?

[jtboofle]

Support for DB2 would be great, though my situation is probably pretty unusual -- I doubt too many people are running CI on an IBM iSeries. I actually ended up making native database calls (it looks a lot like PDO, but even more of a pain) and not using the ActiveRecord tools at all. I might try to wrap my code in something that's more general-purpose, but right now it's not fit for public consumption.

Moving the database code out helps everyone who has funky database issues. I wrote (and re-wrote) my data access libraries repeatedly trying to get something that would work well on the iSeries but once I had the database calls moved out of the session class, I didn't have to muck around in there again. I just overrode the model.

[qrool]

@jtboofle
I`ve got similar thing I run some apps on Tomcat/Quercus env. I need to have an access to java backend because we have SOA env. running lots of hubs and adapters with heavy data load.
In my case I have php-java mapper/driver extended by models (where java backend deals with DB using hibernate) Updating the session table is done by Auth model (it loads user_session_model), I gave up with updating user_session table using Session lib.

[timw4mail]

Picky, but the style guide says to surround ! with spaces.

[narfbg]

The Session class has been drastically changed since this PR was submitted and to be honest - I don't think this is the right approach at all.
Also, DB2 is supported via PDO in develop.