title: Issue with storing date value into a variable in postgresql script
body: <p>I'm trying to fetch first date and last date of month and trying to store the values into the <code>start_date</code> and <code>end_date</code> variables. But, it is not happening?! The output just says <code>DO</code>.</p>
  <pre><code>do $$
  declare 
  start_date DATE;
  end_date DATE; 
  begin
  -- select the first date of the month
     select cast(date_trunc('month', current_date) as date)
     into start_date
     raise notice 'The first date of the month is: %', start_date;
  
  -- select the last date of the month
     select (date_trunc('month', now()) + interval '1 month - 1 day')::date as end_of_month
     into end_date
     raise notice 'The last date of the month is: %', end_date;
  -- show the first and last date of the month   
  end $$;
  </code></pre>