Not null

Sometimes you can be sure something's not null, but Kysely isn't able to infer it. For example calling where('last_name', 'is not', null) doesn't make last_name not null in the result type, but unless you have other where statements you can be sure it's never null.

Kysely has a couple of helpers for dealing with these cases: $notNull() and $narrowType. Both are used in the following example:

import { Playground } from '../../../src/components/Playground'

import { notNull } from './0051-not-null'

:::info[More examples] The API documentation is packed with examples. The API docs are hosted here, but you can access the same documentation by hovering over functions/methods/classes in your IDE. The examples are always just one hover away!

For example, check out these sections:

select method
selectAll method
selectFrom method :::