create table tasks (
  task_id uuid not null,
  process_id uuid not null,
  process_definition_name text not null,
  task_definition_name text not null,
  start_time timestamptz not null,
  end_time timestamptz,
  previous_attempt_count integer not null,
  log_entries ,
  metadata_entries ,
  execution_state ,
  status text references task_statuses not null
);

comment on column tasks.execution_state is '
  Internal bookkeeping metadata used for task scheduling (e.g. ECS task ID and cluster name)
';