On Sunday, January 26, 2020 at 4:48:26 AM UTC-8, Tiago Cardoso wrote:
>
> Hi there,
>
> I've been struggling to find examples on how to do atomic
> increment/decrement operations on a column, which may or may not update the
> "updated_at" timestamps.
>
> Specifically, something like the AR#increment and AR#decrement methods,
> which result in smith like this:
>
> "UPDATE this_table SET counter = COALESCE(counter, 0) + 1"
>
A basic translation of the query:
DB[:this_table].update(:counter=>Sequel.expr{COALESCE(:counter,0)+1})
In general, true updated_at timestamps should be implemented via triggers,
in which case you shouldn't need more than the above to also update that
column. However, if you don't want to use triggers:
DB[:this_table].update(:counter=>Sequel.expr{COALESCE(:counter,0)+1},
:updated_at=>Sequel::CURRENT_TIMESTAMP)
Thanks,
Jeremy
--
You received this message because you are subscribed to the Google Groups
"sequel-talk" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to [email protected].
To view this discussion on the web visit
https://groups.google.com/d/msgid/sequel-talk/45b88fee-a458-463d-a5b3-82b7af3b6e7d%40googlegroups.com.
