Issue: Database Abstraction

Rather than waste memory and speed making a schema translation system for different database types (MySQL, MSSQL, PostgreSQL, etc), instead we will just encapsulate queries in functions, test the database type and then load the appropriate queries file.

Instead the wrapper will just allow field and table name translations between products and map database methods to the appropriate product's database class.

That much is complete.

Looks like IPB uses a similar method for a schema translation system to what I originally had in mind. In order to support IPB, we'll have to develop this after all, so I'm reopening the task for further work.

Using IPB as a model, I was able to complete the main layer. IPB included some features we don't need, so we didn't add support for them. However, we needed to add support for the following which wasn't possible in default IPB:

• Sub-queries
• CASE -> WHEN -> THEN -> ELSE statements
• Multi-table DELETE commands
• consistent table/field escaping

Still have to add support for db_alter, which is weak in IPB compared to vBulletin (no automatic error checking).

DB_alter support added; database abstraction layer complete. Ported and partially rewrote vBulletin's db_alter class to also add support for some things it was missing:

• ADD/DROP PRIMARY KEY
• CREATE/DROP TABLE
• CHANGE COLUMN