I have a record with a integer field score
and I want to perform a decrement update operator like instead of SET "score" = q0."score" + $1
I want to do SET "score" = q0."score" - $1
.
I looked up update
operator with inc
but it doesn’t seem get the expected output that I want
defp reset_vote_multi(multi, query, existing_vote) do
multi
|> Multi.update_all(
:reset_query_vote,
query,
inc: [score: existing_vote.score]
)
end
The problem with my code above, since update/3
will only perform a decrement if existing_vote.score
is negative which I don’t want to do.
Is there a way to perform a decrement on the current field value? I would like to ask for help or ideas.
Thank you.