Database management systems notes
Data Models & Keys
How data can be shaped, why relations won, and the keys that hold a schema together. Every section is a drawn page beside a clear written explanation, about 21 minutes in all.
- Chapter 3 of 34
- About 21 minutes
- 8 sections
Sign in with Google or GitHub and you land straight on this page. DSA comes with the all labs plan and every ChaiCode batch.
In this chapter
- What a data model is
- The models before relational, and why they lost
- The relational model, precisely
- Super keys and candidate keys
- Primary keys and alternate keys
- Foreign keys: how tables connect
- NULL: the value that is not a value
- The two integrity rules
Next chapters
Read the whole chapter
Sign in and the chapter opens with every drawn page, and all 35 database management systems chapters beside it.
DSA comes with the all labs plan and every ChaiCode batch.