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hmm, the facts for a card/many are [e a v ...], where v is a single value


I would understand [e a vs ...] for a :db.type/listOfString (or something..)


@tomjack it stores multiple datoms of that shape (remember Datomic has a universal schema), but it does return a collection e.g. In pull or entity. That universal schema is what enables positional binding to be consistent for every clause in query, among other things.


An ordered list of strings (or any type of data) is essentially a feature request, and one with several applications (including composite keys), but it's a different semantic from card many.


How can I apply missing? to backwards attribute?

'[:find ?e
  [?e :loction/code]
  [(missing? $ ?e :location/_children)]]
I want to find some root entities that has no parent(`_children`)


Does anyone know what the backupPaceMsec property means exactly? The doc says "setting this value to an integer will cause backup to pause that many milliseconds between backup operations", but I'm not sure what a "backup operation" is. Is it querying a single segment, multiple segments, the whole table, or is it something else entirely? I'm using a MySQL backend.


@noziar: it’s paced per segment copied. Most significant with e.g. DynamoDB where it’s otherwise really simple for backup/restore to exceed provisioning when it runs at full tilt. If your storage can’t keep up with the copy/write volume, that’s when you look at upping that settings.


@bkamphaus: thanks for the answer! That does indeed correspond to my observations