Alexander Kuznetsov : Denormalization

Denormalizing to enforce business rules: Running Totals

Alexander Kuznetsov — Fri, 23 Jan 2009 19:57:00 GMT

Calculating running totals is notoriously slow, whether you do it with a cursor or with a triangular join. It is very tempting to denormalize, to store running totals in a column, especially if you select it frequently. However, as usual when you denormalize,...(read more)

Denormalizing to enforce business rules: Part 1.

Alexander Kuznetsov — Wed, 21 Jan 2009 23:49:00 GMT

You cannot use CHECK constraints to compare columns in different rows or in different tables, unless you wrap such functionality in scalar UDFs invoked form a CHECK constraint. What if you actually need to compare columns in different rows or in different...(read more)