Postgres 14

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create table person (id char(1), my_value smallint);

CREATE TABLE


insert into person values
   ('1', 1),
   ('2', NULL),
   ('3', 3)
;

INSERT 0 3


update person as db_record_to_update
set my_value = db_record_new.my_value
from (values
   ('1', NULL::smallint),
   ('2', NULL)
) as db_record_new(id, my_value) 
where db_record_new.id = db_record_to_update.id;

UPDATE 2