Postgres 13

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create table if not exists employee (
    -- id serial primary key,
    id int generated always as identity,
    name varchar(255)
);

CREATE TABLE

insert into employee (name) values ('a'), ('b');
select * from employee;
delete from employee;
insert into employee (name) values ('a'), ('b');
select * from employee;

INSERT 0 2

id
name

1
a

2
b

SELECT 2

DELETE 2

INSERT 0 2

id
name

3
a

4
b

SELECT 2

insert into employee (name) values ('a'), ('b');
select * from employee;
truncate table employee restart identity;
insert into employee (name) values ('a'), ('b');
select * from employee;

INSERT 0 2

id
name

3
a

4
b

5
a

6
b

SELECT 4

TRUNCATE TABLE

INSERT 0 2

id
name

1
a

2
b

SELECT 2