SQLite support (again)

[Ade Lovett]

On 5/15/2012 07:20, Mark Johnston wrote:
> I split them into four actual patches; patches 1-3 in the current set
> are essentially identical to patches 2-4 in [1]. Patch 4 adds column
> names to all the webui ds queries, and also replaces the MDB2 code. As
> before, I'll be happy to maintain SQLite support, and I'll also be
> willing to submit updates to the README.
>
> The patches are here:
> http://www.student.cs.uwaterloo.ca/~m6johnst/patch/tb_sqlite/

I've looked at the patches, and they'd need to be somewhat reworked to 
provide for a "better" upgrade path.

For example:

step 1:  conversion from MDB2->PDO.  this is a big step in its own right 
(and one that I'd heartily support, and have even looked at doing 
myself).  But more importantly, it should _only_ be MDB2->PDO 
conversion, with no reference at all to new backend SQL drivers.

Part of this step would also to be changing the required dependencies in 
order to implement a PDO-enabled webui, along with any appropriate 
documentation changes.  Given the way in which PDO operates, part of the 
conversion would also require the '... AS <foo>' changes to the SQL 
statements that are then passed to the underlying TinderboxDS.pm calls.

step 2:  addition of the ability to use SQLite as a backend, in addition 
to the existing mysql/postgresql backends.  This would include the 
SQLite-specific schemas in sql/*, and tweaks to db_init _and_ the 
(now-using-PDO webui) to allow SQLite to be used as a backend.


This approach makes the relevant patches/commits that much more atomic 
and easier to manage, rather than the existing set of 4 patches that 
have lots of inter-dependencies amongst themselves.

If you can rework things this way, then I'm more than happy to set up 
some test instances, verify that they work (first the MDB2->PDO 
migration, and then the addition of an SQLite backend), and perform the 
relevant commits.

-aDe