How sequelize.fn works?

Question

ORM

I read the doc, read the source code, googled carefully, but could not understand the power of this function. Does it call functions written inside the database (like those created through create functionpostgres) + some built-in ones, or does it allow you to write custom functions at the code level that extend the behavior and allow you not to introduce logic into the database?

Answer 1

First option. Here is an example from their docs

Model.findAll({
  attributes: 
});

In practice, it is easier to use sequelize.queryand in general, the fewer sequelizations, the better. Debugging it is still an adventure. Especially if someone actively used scope and instance methods.

Answer 2

Here is an example.
How would you write this method without fn?