1st Normal Form (1NF)

To be compliant with first normal form, a database table simply needs to follow 2 rules:

It must have a unique primary key.
A cell can't have a nested table as its value (depending on the database you're using, this may not even be possible)

Example of NOT 1st Normal Form

name	age	email
Lane	27	lane@boot.dev
Lane	27	lane@boot.dev
Allan	27	allan@boot.dev

This table does not adhere to 1NF. It has two identical rows, so there isn't a unique primary key for each row.

Example of 1st Normal Form

The simplest way (but not the only way) to get into first normal form is to add a unique id column.

id	name	age	email
1	Lane	27	lane@boot.dev
2	Lane	27	lane@boot.dev
3	Allan	27	allan@boot.dev

It's worth noting that if you create a "primary key" by ensuring that two columns are always "unique together" that works too.

You Should Almost Never Design a Table That Doesn't Adhere to 1NF

First normal form is simply a good idea. I've never built a database schema where each table isn't at least in first normal form.

Assignment

We hired an intern at CashPal and her first task was to design a new "companies" table. This table will store our business client's data. Unfortunately, the intern has committed the unforgivable sin - there's no primary key on this table! We could have entire duplicate rows!

Add an id field as the first column. It should be an integer and have a PRIMARY KEY constraint on it. When you're done, the companies table will be in first normal form.

CREATE TABLE companies (

name TEXT NOT NULL,

num_employees INTEGER NOT NULL

);