I am current in planning on creating a big database (2+ million rows) with a variety of data from separate sources. I would like to avoid structuring the database around auto_increment ids to help prevent against sync issues with replication, and also because each item inserted will have a alphanumeric product code that is guaranteed to be unique - it seems to me more sense to use that instead.

I am looking at a search engine to index this database with Sphinx looking rather appealing due to its design around indexing relational databases. However, looking at various tutorials and documentation seems to show database designs being dependent on an auto_increment field in one form or another and a rather bold statement in the documentation saying that document ids must be 32/64bit integers only or things break.

Is there a way to have a database indexed by Sphinx without auto_increment fields as the id?