From Records to Databases
Move from ordinary files to explicit relationships, enforceable rules and useful questions.
Files, Folders and Data Formats
You will separate the location of a file from the identity of its contents and the identity of the records inside it. You will follow bytes through…
8,385 words/36 min read8Why Databases Exist
You will explain the shared-file problem without claiming that ordinary files are useless. You will distinguish stored data, a database engine and the…
8,066 words/35 min read9Tables, Rows and Relationships
You will describe a table as a collection of claims with a defined row meaning, not merely a grid of cells. You will distinguish a column’s storage type…
8,131 words/35 min read10Designing a Schema That Matches the Work
You will turn a description of somebody’s work into a small set of records with explicit meanings. You will separate the question “what do people need to…
8,380 words/36 min read11Constraints: Rules the Database Can Enforce
You will explain a constraint as an enforced acceptance rule, not merely a note beside a field. You will distinguish a required value from a check on…
8,318 words/36 min read12SQL From Zero: Asking Your First Questions
You will read a small SELECT statement as a question about named records rather than a mysterious command. You will choose explicit output columns and…
8,529 words/37 min read13Joins and Normalisation: Putting Facts in the Right Place
You can now create tables and ask questions of one table. This chapter explains how to divide information between tables without losing its meaning, and…
5,573 words/24 min read