Re: Query slow again after adding an `OR` operation (was: Slow PostgreSQL 10.6 query)

Are you prefixing this auto generated query with set join_collapse_limit =
30, or are you changing the default and reloading config? That is, can you
impact ONLY this query with these config changes? I wouldn't assume so, so
any hack/query hint like turning off hashjoins (which seem to be chosen
instead of nested loop because of bad estimates for this plan) will likely
have serious impact on other queries.

I know you don't have the flexibility to change the query to be one that
follows best practices, but it is a bit disappointing that your ORM
generates that OR condition instead of something like *brs.branch_id IN
(query1 union all query2). *The join to branch_invoices also must function
as inner join rather than left, but I am not sure if declaring a join type
as left impacts the performance significantly.

When performance matters, there's nothing quite like being able to
customize the query directly.