Mod_ReWrite / ReWriteMap a URL using a database lookup script

Question

The Scenario
I have completely rewritten an old existing ASP classic ecommerce website over to PHP.

The database design of the previous site had

Answer 1

Your query:

SELECT
  ID
FROM
  thetable
WHERE
  ProductID=?

From there just echo the value of ID and a newline, and flush stdout.

Rewrite rules:

RewriteMap dbfixup prg:dbfixup.script
RewriteCond %{QUERY_STRING} ProductID=(\d+)
RewriteRule Product.asp Products.php?ID=${dbfixup:%1}