How to correct the request to prometheus to remove the columns from the resulting table?

Question

Monitoring

I do monitoring according to the article POWA-like monitoring PostgreSQL using Prometheus https://habr.com/ru/post/345370/

The request is like this

topk(10, increase(pg_stat_statements_calls{datname!~"template.*", datname!~"postgres", instance=~"$server", datname=~"$database"}[10m]))

How to correct the request to prometheus to remove the columns from the resulting table? For example columns alias, server.
What tag to put for metrics?