From the Certified Developer course, you can see the left join to include fields from the SU_EXTENTION_DATA table. Why is the MAX used when retrieving these values???
! Custom begin -------------------
LEFT JOIN
(SELECT
REF_NO "REF",
MAX(CASE WHEN EXTENSION_FIELD_REF = 500033 THEN VALUE_DATE END) "DOB",
MAX(CASE WHEN EXTENSION_FIELD_REF = 500034 THEN VALUE_STRING END) "E_CONTACT",
MAX(CASE WHEN EXTENSION_FIELD_REF = 500035 THEN VALUE_STRING END) "E_CONT_NO",
MAX(CASE WHEN EXTENSION_FIELD_REF = 500036 THEN VALUE_TEXT END) "MED_HIST",
MAX(CASE WHEN EXTENSION_FIELD_REF = 500037 THEN SELECT_TEXT END) "PREF_CONTACT"
FROM SU_EXTENSION_DATA
LEFT JOIN SU_SELECT_VALUES ON
SU_EXTENSION_DATA.VALUE_SELECT = SU_SELECT_VALUES.REF
WHERE CORE_ENTITY = 5
GROUP BY REF_NO) X ON AR_PERSON.REF = X.REF
! Custom end -------------------