I don’t think the database is well designed, but I know the database design is not from you. ;-)

I can understand why there are three tables, and I actually agree that’s a must, if you want to make the price-product info fully normalized.

But the data in price-type table should be only used for two purposes:
  1. As a data integration reference, we can use it to check and make sure all price-id’s in all other tables are valid, i.e. there is row in this table for that price-id.
  2. Store the visual presentation for each price-id, for example, if you want to print some report, instead of showing the less meaningful price-id, you may want to show the price type.
But to use price-type as part of unique keys elsewhere is a bad idea. Only price-id should be used for that purpose.

In the product-price table, instead of storing price-type, should storing price-id, and form unique index together with product-id.

In reply to Re: Database design and Class::DBI by pg
in thread Database design and Class::DBI by Ovid

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