In my Postgresql schema I have a jobs table and an accounts table. Once a day I need to schedule a job for each account by inserting a row per account into the jobs table. This can done using a simple INSERT INTO.. SELECT FROM statement, but is there any empirical way I can know if I am straining my DB by this bulk insert and whether I should chunk the inserts instead?
Postgres often does miraculous work so I have no idea if bulk inserting 500k records at a time is better than 100 x 5k, for example. The bulk insert works today but can take minutes to complete.
One additional data point: the jobs table has a uniqueness constraint on account ID, so this statement includes an ON CONFLICT clause too.