rarrrrrr

  => SELECT 'hello' AS var1, 10 AS var2
  -> \gset
  => \echo :var1 :var2
  hello 10

  testdb=> \set content `cat my_file.txt`
  testdb=> INSERT INTO my_table VALUES (:'content');

  create table user_email (
      email text not null 
  );
  -- create a index on the lowercase form 
  -- of the email 
  create unique index user_email_case_idx 
      on user_email (lower(email));
  -- select using the index, with the lowercase form.
  select 1 
    from user_email 
   where lower(email)=lower('[email protected]');