The correct database module for Nest.js - https://blog.entrostat.com/setting-up-a-database-module-in-nest-js/

database.module.ts

import { TypeOrmModule } from '@nestjs/typeorm';
import { databaseConnections } from './database-connections';
import { Module } from '@nestjs/common';

@Module({
    imports: [
        ...databaseConnections
    ],
    exports: [
        TypeOrmModule
    ]
})
export class DatabaseModule {}