title: SQL get all entries by ids
body: <p>I have 3 tables roughly like below:</p>
  
  <pre><code>create table user(
      id integer primary key
  )
  
  create table post(
      id integer primary key,
      author integer,
      foreign key (author) references user(id)
  )
  
  create table user_following(
      id integer primary key,
      follower integer,
      followee integer,
      foreign key (follower) references user(id),
      foreign key (followee) references user(id)
  )
  </code></pre>
  
  <p>these tables were created by ORM framework, I want to use raw SQL to get all posts by a user's <code>followee</code>, which can be multiple users. Can I do it in SQL?</p>