i am using nestjs and trying to add an auto Increment column by typeorm and mongodb driver but nothing happed and also the column not created and that is my commands

import { Column, Entity, Generated, ObjectIdColumn } from "typeorm";

@Entity({name : 'employees'})
export class Employees {
    @ObjectIdColumn()
    id : string  
    
    @Column({type : 'string'})
    userName : string 
    
    @Column({type : 'string'})
    fullName : string 

    @Column()
    @Generated('increment')
    employeeID : string

is that feature available in mongodb or only mysql