I have a table (People) with columns (id, name, year). Is there any way I can get all the ids (
SELECT id FROM people
Well, usually you have information on a person and write one record with this information. It makes litte sense to write empty records for all persons. Moreover, when it's just one record per person, why not simply add an information column to the people table?
Anyway, you can create mock records thus:
insert into people_info (people_id, additional_info) select id, null from people;