Comment by Dylan16807
21 hours ago
Would GROUP BY fix the issue?
The article explains that skip scan doesn't do anything here.
> nor does it imply the author knew about indexes, nor ANALYZE
Indexes were talked about a lot, and they explicitly mentioned looking at the query plan.
The article seems to have changed since I commented.
https://web.archive.org/web/20260814160231/https://www.dbos....
It had the same stuff a month ago.
Why don't he use GROUP BY on indexed columns was my first thought also.
I guess we just have to patiently wait for the OP to hopefully read Postgres documentation from postgreSQL 10.x before correcting the article again.
> Why don't he use GROUP BY on indexed columns was my first thought also.
Because it has the same issue.
SELECT DISTINCT and GROUP BY are equivalent from a query planner perspective.
Does that fix it? Why would people be trying to add new index scanning modes if that's enough to fix it?
Someone else said it doesn't.
nope - either gets you a HashAggregate, GroupAggregate, or Unique depending on whether the column/input is indexed/ordered