DO — execute an anonymous code block
DO [ LANGUAGElang_name]code
   DO executes an anonymous code block, or in other
   words a transient anonymous function in a procedural language.
  
   The code block is treated as though it were the body of a function
   with no parameters, returning void.  It is parsed and
   executed a single time.
  
   The optional LANGUAGE clause can be written either
   before or after the code block.
  
code      The procedural language code to be executed.  This must be specified
      as a string literal, just as in CREATE FUNCTION.
      Use of a dollar-quoted literal is recommended.
     
lang_name      The name of the procedural language the code is written in.
      If omitted, the default is plpgsql.
     
   The procedural language to be used must already have been installed
   into the current database by means of CREATE LANGUAGE.
   plpgsql is installed by default, but other languages are not.
  
   The user must have USAGE privilege for the procedural
   language, or must be a superuser if the language is untrusted.
   This is the same privilege requirement as for creating a function
   in the language.
  
   Grant all privileges on all views in schema public to
   role webuser:
DO $$DECLARE r record;
BEGIN
    FOR r IN SELECT table_schema, table_name FROM information_schema.tables
             WHERE table_type = 'VIEW' AND table_schema = 'public'
    LOOP
        EXECUTE 'GRANT ALL ON ' || quote_ident(r.table_schema) || '.' || quote_ident(r.table_name) || ' TO webuser';
    END LOOP;
END$$;   There is no DO statement in the SQL standard.