fix

things/nest-typeorm-init/src/app.service.ts

 import { Injectable } from '@nestjs/common';
 import { AppLogger } from './app.logger';
-import { Connection, Repository } from 'typeorm';
+import { Connection } from 'typeorm';
 import { InjectConnection } from '@nestjs/typeorm';
 
 @Injectable()
 export class AppService {
   constructor(
-    @InjectConnection('waitress')
+    @InjectConnection('app')
     private db: Connection,
     private log: AppLogger,
   ) {