Thank you for your comments. I attached the fixed patch below.

On 09/20/2014 14:16, Nicolas Goaziou wrote:
> This is not related to your patch, but while you're at it, use `delq' 
> instead of `remq' (nitpick) and `dbstring-postgresql' needs to be 
> renamed `org-babel-sql-dbstring-postgresql' or some such. 
I used mysql parameters handling code as a template for writing my 
patch, so it suffered from the same problems. I added a second patch 
that renames `dbstring-mysql' to `org-babel-sql-dbstring-mysql' and that 
uses `delq' instead of `remq' in its implementation. I did some basic 
tests to ensure I didn't break anything.

Regards,
Steven Rémot