Value Chain Introduction

For value chain, here introduces 3 models.

Inventory Periodic Model

Scenario: a grocery with 60,000 products * 100 stores, with daily periodic model, there would be 60k*100=6millon records per day.
Estimation
- 14byte per row * 6million =84mb per day ; 3 years will be 84 * 1095day=91G data
- or 60days of daily and archive old data to weekly snapshot;
Semi-Additive Facts
- Pay attention to the use of " SQL AVG" when do summarize
Enhanced Inventory Facts
- Adding more column to fact table including quantity on hand, quantity sold,
  - quantity sold daily / quantity at hand daily = number of turns
  - quantity sold whole year / average quantity at hand daily = number of turns for a year
  - Estimate number of days’ supply = current quantity at hand / average quantity sold per day
- Adding inventory at cost and inventory value at latest selling price

P117