SQL: Update using a select

begin transaction;

update targettable
set "location" = CAST(ST_SetSRID( ST_Point(subquery.longitude_::float, subquery.latitude_::float), 4326) AS geography)
from (
select id, ajsonb -> 'location' as location_, ajsonb->'location'->'latitude' as latitude_, ajsonb->'location'->'longitude' as longitude_
from targettable) as subquery
where targettable.id = subquery.id
and subquery.location_ is not null

commit;
--rollback;