Schema Migration about datahike

[whilo]

Yes, this is unfortunately true. You can also overwrite the schema in the database yourself, if you know that it is consistent with its current value.

(swap! conn assoc :schema new-schema)
(datahike.api/transact! conn [])

should do the trick.

[mgerlach-klick]

Oh, good to know! Thank you @whilo !

[mgerlach-klick]

I don't think this actually works.

I modified a schema to make one attribute :db/isComponent true and swap!ed it in. This had no effect on the queries. I'm guessing I would have to modify (:rschema conn) in some way as well?

[whilo]

@mgerlach-klick Yes, that is true. Did it work for you? I haven't found the time yet to figure it out, but we will aim to fix this over the next months with full schema support.

[mgerlach-klick]

I don't recall. I believe I gave up before I got to that point. Maybe ping me once this is working and I'll give datahike another try?

[px0]

I'm excited about trying v0.2. What's the status on schema migration now?

[px0]

Replying to myself, found this: https://github.com/replikativ/datahike/blob/master/doc/schema.md#migration

[tatut]

Adding new attributes to any :db/ident entities seem to fail

(defn dh-update-exception []
  (let [uri "datahike:mem://test"]
    (datahike.api/create-database uri)
    (let [c (datahike.api/connect uri)]
      ;; Add two enum values
      (datahike.api/transact c {:tx-data [{:db/ident :task.status/in-progress}
                                          {:db/ident :task.status/complete}]})

      ;; Later we realize we want to trac which enum values belong together
      (datahike.api/transact c {:tx-data [{:db/ident :enum/attribute
                                           :db/valueType :db.type/keyword
                                           :db/cardinality :db.cardinality/one}]})

      ;; Then we update existing enum values
      (datahike.api/transact c {:tx-data [{:db/ident :task.status/in-progress
                                           :enum/attribute :task/status}
                                          {:db/ident :task.status/complete
                                           :enum/attribute :task/status}]}))))

Running that will throw:

Update not supported for these schema attributes
   {:error :transact/schema,
    :entity
    {:db/ident :task.status/in-progress, :enum/attribute :task/status},
    :invalid-updates #:enum{:attribute [nil :task/status]}}```