Okay. What is the difference between a fact and a dimension table?

A fact table is the central table in a star or snowflake schema that stores quantitative, measurable data such as sales revenue, units sold, or transaction amounts. It contains numeric measures and foreign keys that reference dimension tables. Fact tables are typically denormalized and can be very large. A dimension table, on the other hand, stores descriptive attributes that provide context to the facts, such as product name, customer demographics, or time periods. Dimension tables are usually smaller, contain textual or categorical data, and are used for filtering, grouping, and labeling in reports. The key difference is that facts hold the metrics you want to analyze, while dimensions provide the descriptive context that allows you to slice and dice those metrics.