updating a primary key field

[Sander Plas]

In jOOQ 1.6.1, changing the value of a primary key field on an
existing record results in a new insert.

Record from my 'ledger' table, primary key is on column 'code':

 code |              description
------+---------------------------------------
 M1   | test description


This works OK:

record.setDescription("blabla");
record.store();

PostgreSQL log:

update "public"."ledger" set "description" = $1 where
"public"."ledger"."code" = $2
parameters: $1 = 'blabla', $2 = 'M1'


This doesn't:

record.setCode("test");
record.store();

PostgreSQL log:

insert into "public"."ledger" ("code", "description") values ($1, $2)
parameters: $1 = 'test', $2 = 'blabla'


Is this a bug or a feature? :)