1. **Database (Operational Database / OLTP):** - **Purpose:** Runs the day-to-day operations of a business. Designed for fast recording and retrieval of individual transactions. - **Data:** Current, detailed, up-to-the-minute. - **Example:** An online store's database that processes customer orders, updates inventory in real-time, and manages user accounts. 2. **Data Warehouse (OLAP):** - **Purpose:** Analyzes business performance over time to support decision-making. Designed for complex queries and reporting on large amounts of historical data. - **Data:** Historical, aggregated, summarized, often integrated from multiple databases. - **Example:** Analyzing sales trends from the past 5 years across different regions and product categories, using data pulled periodically from the store's operational database, marketing systems, etc. - Semantics are harder to implement in data warehouses. #### Matrix of Fact Think of it as a **high-level blueprint or grid** used during the design phase of a data warehouse. Here's the breakdown: 1. **Purpose:** To visualize and plan the scope and integration points of the data warehouse across different business processes. 2. **Structure:** - **Rows:** Typically represent **Business Processes** (e.g., Sales Orders, Inventory Shipments, Customer Support Calls). Each row often corresponds to a planned **Fact Table**. - **Columns:** Typically represent common **Business Dimensions** (e.g., Date/Time, Product, Customer, Store, Employee). These correspond to planned **Dimension Tables**. 3. **Intersections (Cells):** The checkmarks or entries within the grid cells indicate where a specific **Dimension** is relevant to and participates in a specific **Business Process** (and thus will be linked to the corresponding Fact Table). #### مثال - در هر ساعت مقدار ترافیک در منطقه x چه مقدار است؟ - کدام خیابان کمترین میزان ترافیک در روز را داشته؟ - میانگین هفتگی ترافیک برای منطقه x در سال افزایشی بوده یا کاهشی؟ فکت: میزان ترافیک کوالیفایر:‌ روز، ساعت، منطقه، ### معماری‌های مفهوم انبازش داده - ستاره Star - دانه برف Snowflake - مدل گلکسی Galaxy