Looking for minimal SQL

[Marco Aschwanden]

Hi

I would like to develop an app that is (more or less) database independet. 
Python DB API helps when masking "parameters" of sql statements. The db 
driver cares for the correct conversion of a date, text, etc. This already 
is a big step into the right direction.

The next step would be to use the least common denominator of all sql 
dialects and do without all the sql goodies that the dialects offer... and 
for this part I am wondering if anyone has a link / hint / book that 
assembled this minimum sql. I am looking for something that says for 
example:

Table/DB Design: always use lowercase letters, ...

Allowed sql functions: min, max, count

WHERE / HAVING hints:
- Don't use subselects

The focus is actually limited to SELECT / INSERT / UPDATE / DELETE (I 
don't think that GRANT / CREATE XXX / ... statements are very portable).

I am aware, that a solution created this way is not as fast and as elegant 
as an app that uses all features of a dialect, but I am really looking for 
something database independent...

Thanks for any hints,
Marco