MySQL 8.0

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create table newtable as select 1 as id

Records: 1  Duplicates: 0  Warnings: 0

alter table newtable add column hash_code varchar(32) as
     (md5(id))

Records: 0  Duplicates: 0  Warnings: 0

select *
from newtable

id
hash_code

1
c4ca4238a0b923820dcc509a6f75849b

insert into newtable (id) values (100)
select *
from newtable

id
hash_code

1
c4ca4238a0b923820dcc509a6f75849b

100
f899139df5e1059396431415e770c6dd

id	hash_code
1	c4ca4238a0b923820dcc509a6f75849b
100	f899139df5e1059396431415e770c6dd