text: CREATE TABLE files (
    id bigint NOT NULL,
    access_salt text NOT NULL,
    s3_upload_key text NOT NULL,
    is_uploaded boolean default false NOT NULL,
    PRIMARY KEY (id)
  );
  
  CREATE INDEX on files(s3_upload_key);
  
  CREATE TABLE file_parts (
    file_id bigint NOT NULL,
    number int NOT NULL,
    size int NOT NULL,
    s3_upload_key text NOT NULL,
    PRIMARY KEY (file_id, number)
  )