 
 CREATE TABLE addresses (
     id integer NOT NULL,
-    addressable_type character varying,
-    addressable_id integer,
+    addressable_type character varying NOT NULL,
+    addressable_id integer NOT NULL,
     street_1 character varying,
     street_2 character varying,
     county character varying,

    paediatric_patient_indicator boolean,
    sex character varying,
    ethnicity_id integer,
    current_address_id integer,
    address_at_diagnosis_id integer,
    gp_practice_code character varying,
    pct_org_code character varying,
    hospital_centre_code character varying,

    family_name character varying,
    email character varying,
    code character varying,
    practitioner_type character varying NOT NULL,
    created_at timestamp without time zone NOT NULL,
    updated_at timestamp without time zone NOT NULL,
