I'm working on a similar project (Access, Oracle, and Sybase, with SQL Server to come), and here's what we've found, as far as I know:<BR><BR>Mostly ANSI SQL will convert without changes.

-- Get the session time zone. -- Find the next week’s date from SYSDATE. -- SELECT SYSDATE+7 AS NEXTWEEK_DATE FROM DUAL -- Subtract 17 days from SYSDATE. -- SELECT SYSDATE-17 AS 17DAYSBACK FROM DUAL - ...