There are nicer ways to do batch insert in postgres.

With 'jsob_to_recordset' there is only one parameter which is an array and it gets queried as a table. That has the advantage of avoiding different queries for different inputs (it can be prepared only once, it's harder to commit mistakes...). Also it doesn't have the overhead of creating a huge string.

Another option is copy to. Using pg copy node https://github.com/brianc/node-pg-copy-streams you can insert/query as much as you want from/to node streams without memory footprint. I've used it to pipe millions of records straight to an http response (to download a csv)