In my PostgreSQL database I have a ema schema and 10 tables for different timeframes for which EMAs were calculated: ema.ema_1s, ema.ema_1min etc.

In TypeORM each entity is created with specified name and used as Repository<Entity> inside a service.

I’ve created Ema entity:

import { Column, Entity, PrimaryColumn } from 'typeorm';

@Entity({ schema: 'ema' })
export class Ema {
  @PrimaryColumn({ type: 'text' })
  symbol: string;

  @PrimaryColumn({ type: 'text' })
  exchange: string;

  @Column({ type: 'double precision' })
  ema: number;

  @PrimaryColumn({ type: 'timestamp' })
  timestamp: Date;
}

Is there a way to use this entity for each table inside ema schema or I should create separate entities for each table like:

@Entity('ema_1s', { schema: 'ema' })
export class Ema1s extends Ema {}

@Entity('ema_1min', { schema: 'ema' })
export class Ema1min extends Ema {}
...

And use them in code like this:

import { Injectable } from '@nestjs/common';
import { InjectRepository } from '@nestjs/typeorm';
import { Repository } from 'typeorm';

import { Ema1min, Ema1s } from '@/common/entities';

@Injectable()
export class PostgresService {
  constructor(
    @InjectRepository(Ema1s)
    private readonly ema1sRepository: Repository<Ema1s>,
    @InjectRepository(Ema1min)
    private readonly ema1minRepository: Repository<Ema1min>,
    ...
  ) {}
}

This approach seems to me not really suitable because I have 10 different tables for ema and 3 other schemas, so there will be 40 different injections so I can use all the tables.