use session_class in database tasks

[chaadow]

@rafaelfranca BTW I believe this can be simplfied to only where( created_at < ?, cutoff_period)

the example in the rails guides, uses a different period for each column where(updated_at: ...time.ago).or(where(created_at: ...2.days.ago)).delete_all) ( check : https://guides.rubyonrails.org/security.html#session-expiry )

I'm in favor of only keeping created_at and adding an index on that column instead of an index on updated_at because adding an index on updated_at ( a column which is constantly/naturally updated almost every single time) prevents Heap Only Tuple (HOT ) updates on PostgreSQL, which can lead to write amplification / more WAL etc...

[chaadow]

@rafaelfranca also would you mind me using in_batches(use_ranges: true) to further optimize the SQL queries and make them index-only scans, otherwise the sorting is using the primary key ( id) by default

[rafaelfranca]

No. Let's use in batches as well