don't save foreign key relationships for "the end"

consider adding foreign keys part of creating a table; if you haven't set up foreign key relationships, you haven't finished creating your table.

indexes, on the other hand, can be saved for "the end", once you get a better sense of how you're querying the tables and what's most optimal. but even with indexes, if you have a good sense when you're creating the table of how you're most likely to access the data, you're better off taking an educated guess early than never doing it late--