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create distinct type person_id_type as integer with comparisons;
create distinct type address_id_type as integer with comparisons;
create table person
(
id person_id_type not null primary key,
name varchar(100) not null
);
create table address
(
id address_id_type not null primary key,
person_id person_id_type not null references person,
info varchar(100) not null
);
-- works because the join columns have the same "distinct" type
select p.*
from person p
join address a on a.person_id = p.id;
-- fails
select p.*
from person p
join address a on a.id = p.id;
[IBM][CLI Driver][DB2/LINUXX8664] SQL0401N The data types of the operands for the operation "=" are not compatible or comparable. SQLSTATE=42818 SQLCODE=-401