Changing the schema for large relational databases costs companies [millions of dollars] every year. Relational databases are highly intertwined, so one small change can have unexpected, cascading effects.

The foundation for a table in a relational database is the primary key. Because of its importance, we have to give special consideration to how we select our primary keys.

Table of Contents:

1. [Understanding Keys in SQL]
2. [Creating a Primary Key with PostgreSQL]
3. [A Universally Unique ID? Intro to UUIDs]
4. [Creating a UUID Primary Key Using  - PostgreSQL Example]
5. [Alternative to UUID - Auto-Increment Primary Key]
6. [UUID vs Auto-Increment Primary Key]

#postgresql #schema #uuids