Just randomly came across my head. I've built a few system in the past that deal with inventory. And usually I calculate the inventory by summarizing the sum of all inventory transaction record. The downside is that the bigger the database is the slower the performance gets, this will eventually happen due to inventory is usually a high transaction database.
Wondering what is the best practice out there? Do you store the inventory count as a number, or do you calculate everytime you need it? Or is there some other very creative way?