Consider making allowNull: false the new default

[ephys]

I don't think everyone is going to agree with me on this (feel free to express your opinion with the 👎 and 👍 reactions), but I think that nowadays we tend to be a lot stricter regarding what can and cannot be null.

My main reason for this change is that it would be better aligned with TypeScript. You'd only specify allowNull if you also made your type nullable:

class User extends Model {
  firstName: string,
}

User.init({ firstName: string });

// &

class User extends Model {
  firstName: string | null,
}

User.init({ firstName: { type: string, allowNull: true } });

But I also think that in most cases, it's safer to make the application crash when null accidentally got in a field that was accidentally left nullable, than having incomplete data in the database.

To ease migration, I would also add an option in the Sequelize constructor to choose whether attributes are nullable by default .

---

TypeORM made this change a few years back, I think we could too.

Past issues related to this:

• Set the default allowNull: false globally #13439
• Why allowNull default value is true? #11030
• Change default value of allowNull for all models #504

[WikiRik]

Would be big breaking change, but I think this is for the best. Good idea to add an option in the constructor so if people want to keep the default nullable they can

[javiermrz]

Hi! Is there any update on this?

[ephys]

It's currently blocked by #14682, which is itself blocked by #14715, which is itself blocked by #14687, which is itself blocked by an issue with describeTable we need to resolve

We'll get there eventually :/

[benasher44]

Hyped for this!

[fpirsch]

Columns are nullable by default in databases. Making the opposite choice in the orm would be weird.
Why align with TypeScript ? Remember GraphQL fields are also nullable by default.