Create CHECK/EXCLUDE constraints using LB4 model/property decorators?

[serkansahinBE]

Hi,

I would like to know if there is a possibility to create constraints of types CHECK and EXCLUDE using LB4's ORM using PostgreSQL connector? Maybe there's already a doc or a topic (I hope)..

For example (a dummy one):

• A model named "Wallet" defined as below:

import {Entity, model, property} from '@loopback/repository';

@model({
    settings: {
        postgresql: {
            schema: 'public',
            table: 'wallet'
        }
    }
})
export class Wallet extends Entity {
  @property({
    type: 'string',
    id: true,
    generated: true,
  })
  id?: string;

  @property({
    type: 'number',
    required: true,
  })
  balance: number;


  constructor(data?: Partial<Wallet>) {
    super(data);
  }
}

export interface WalletRelations {
  // describe navigational properties here
}

export type WalletWithRelations = Wallet & WalletRelations;

Now I want to add a CHECK constraint on the "balance" column let say that it cannot be below 0, so in an SQL query it will be something like this: CREATE TABLE wallet (id SERIAL PRIMARY KEY, balance INTEGER CHECK (balance >= 0)).

As a workaround, I have created a custom function that will create all the constraints by running for example: ALTER TABLE public."wallet" ADD CONSTRAINT check_balance_below_zero CHECK (balance >= 0);, but I'd like to stay ISO with the framework's ORM and if it is possible to add/create CONSTRAINTS using it.
Thanks :)