Hash Partitioning on primary key (long) doesn't work

[MaksimSimkin]

We have a class With Primary Key Id (long) and we want to have hash partitions on this table:

    public class Stuck
    {
        public long Id { get; set; }
...
    }

            var hashValues = Enumerable.Range(0, NumberOfPartitions)
                .Select(i=>$"mt_doc_stuck_part_{i:00}")
                .ToArray();

            options.Schema.For<Stuck>()
                .PartitionOn(x=>x.Id, x=>x.ByHash(hashValues));

On SQL generation for this table we are running in issue, that Marten is trying to duplicate Id Column for partitions, having already an id pk column.

[mysticmind]

@MaksimSimkin why would you partition a table using its primary id? You should be partitioning by some other property other than the primary id. Possibly, if you are using Stuck.Id as a foreign key or something in a different table and if you partition that table using say StuckId, it makes sense.

Edit: If you want to use some sort of a partition number then that has to a property on Stuck like PartitionNumber and then you have to partition on it and not on Id

[MaksimSimkin]

@mysticmind If i am doing partition on primary id i have always more or less equal amount of data in each partition, and i don't need to take care if the property i use is distributed the sam equally.
But actually the answer is: because i have it already. We are using marten in Version 3, our huge table has already this partitions and now we want to upgrade marten to latest version without database changes.

[mysticmind]

Got it, you have a pre-existing partition which you created yourself and now you are trying to use the Marten provided partitioning thinking it would seamlessly work. I think, you may want to check what Marten does for partitioning as a logic and get the state of your existing db in the exact similar way to get going.

[mysticmind]

If i am doing partition on primary id i have always more or less equal amount of data in each partition, and i don't need to take care if the property i use is distributed the sam equally.

Makes sense, gotcha!

[mysticmind]

This is not a bug per se. So converting this to a discussion.

[mysticmind]

added back as an issue #4025