Postgre SQL PostgreSQL

postgres=#
postgres=#
postgres=# CREATE TABLE "shipments" (
postgres(#      "id" integer NOT NULL,
postgres(#      "customer_id" integer,
postgres(#      "isbn" text,
postgres(#      "ship_date" timestamp with time zone
postgres(# );
CREATE TABLE
postgres=# insert into shipments values (2,    107,  '0394800753','2001-09-22 20:18:56-07');
INSERT 0 1
postgres=#
postgres=# select * from shipments;
 id | customer_id |    isbn    |       ship_date
----+-------------+------------+------------------------
  2 |         107 | 0394800753 | 2001-09-22 20:18:56-07
(1 row)
postgres=#
postgres=# drop function add_shipment(integer,text);
DROP FUNCTION
postgres=#
postgres=# CREATE FUNCTION "add_shipment" (integer,text) RETURNS timestamp with time zone AS '
postgres'#   DECLARE
postgres'#     customer_id ALIAS FOR $1;
postgres'#     isbn ALIAS FOR $2;
postgres'#     shipment_id INTEGER;
postgres'#     right_now timestamp;
postgres'#   BEGIN
postgres'#     right_now := ''now'';
postgres'#     INSERT INTO shipments VALUES ( 3, customer_id, isbn, right_now );
postgres'#     RETURN right_now;
postgres'#   END;
postgres'# ' LANGUAGE 'plpgsql';
CREATE FUNCTION
postgres=#
postgres=# select add_shipment(1,'newItem');
        add_shipment
----------------------------
 2006-10-09 10:06:16.195-07
(1 row)
postgres=#
postgres=# select * from shipments;
 id | customer_id |    isbn    |         ship_date
----+-------------+------------+----------------------------
  2 |         107 | 0394800753 | 2001-09-22 20:18:56-07
  3 |           1 | newItem    | 2006-10-09 10:06:16.195-07
(2 rows)
postgres=#
postgres=# drop table shipments;
DROP TABLE
postgres=#