Update query to fixed value while joining to multiple tables

Question

We have a lot of phone country codes that are blank or incorrect. For example, Egypt's phone country code is 20. I want to update the phone country code to 20 but only if the country in the locations table = 'EG' and there is in fact a location record (it's possible a party has a phone number but not a physical address in which case there is insufficient information to update the phone country code to 20. Here's what I have thus far which does not work.
update ar.hz_contact_points hzcp
set hzcp.phone_country_code = 20
join ar.hz_party_sites hzps on hzps.PARTY_ID = hzcp.OWNER_TABLE_ID
join ar.hz_locations hzl on hzl.LOCATION_ID = hzps.location_id
where 1=1
and hzcp.owner_table_name = 'HZ_PARTIES'
and hzl.location_id = hzps.location_id
and hzl.country = 'EG'
and hzcp.phone_country_code not like '20'
and hzcp.contact_point_id = '54060443' --(Note I'm limiting it just to one record for testing.)Thanks in advance!

Answer 1

Just slightly different
update ar.hz_contact_points hzcp
   set hzcp.phone_country_code = 20
where hzcp.phone_country_code != 20
   and hzcp.owner_table_name = 'HZ_PARTIES'
   and hzcp.contact_point_id = 54060443   --(Note I'm limiting it just to one record for testing.)
   and exists(select null
                from ar.hz_party_sites hzps,
                     ar.hz_locations hzl
               where hzps.PARTY_ID = hzcp.OWNER_TABLE_ID
                 and hzl.location_id = hzps.location_id
                 and hzl.country = 'EG'
             )Regards
Etbin