Consider the following table:
create table language (
id integer generated always as identity (START WITH 1, INCREMENT BY 1),
name long varchar,
constraint language_pk primary key (id)
);
To which I'd insert an entry this way.
insert into language(name) values ('value');
How does one know what value for id
was created? Just doing a SELECT using the name
field is not valid, because there can be duplicate entries.
Through plain SQL:
insert into language(name) values ('value');
SELECT IDENTITY_VAL_LOCAL();
See the manual for details: http://db.apache.org/derby/docs/10.7/ref/rrefidentityvallocal.html
When doing this from a Java class (through JDBC) you can use getGeneratedKeys() after "requesting" them with the approriate executeUpdate() method.