How to insert 300 rows into a table?

Question

PostgreSQL

How to insert 300 rows into a table:

CREATE TABLE table_Number(
  key integer NOT NULL,
  tstamp timestamptz NOT NULL);

where key is not a primary key and is filled with numbers 1,2,3...300, tstamp - generate_series(NOW() - INTERVAL '90 days', NOW(),'1 min')

Answer 1

Still, it was easier to make key serial.

insert into table_Number (key, tstamp)
select * from (
  select row_number() over () n, t
  	  from generate_series(NOW() - INTERVAL '90 days', NOW(),'1 min') t
  ) sq
 where n <= 300

https://www.db-fiddle.com/f/bzE1G4cQ8S6sCHHPFH64gx/0

Answer 2

insert into