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is there a way to restore a db on windows? I'm having no luck whatsoever, it can't recognise the roots. here are some details:!topic/datomic/YPBFdRl_fI0


We’d like to store audit trail data each time someone updates the value of an attribute on a particular entity (e.g. store the user and datetime for the update). looks promising for this use-case, but I wanted to double check if that's the recommended best-practice for audit trails. I also wondered if anyone has a more elaborate example of adding and retrieving facts from transactions? We want to render the audit data in the UI when a user hovers over the attribute’s text-field. Is there a way to merge the entity data, and the transaction audit trail data into one query? Or would we have to do it as multiple queries, and merge the results ourselves?


@james You might want to watch the Reified Transactions video here


It includes discussion of using transaction metadata for audit trail


I’ll take a look, thank you!


In datomic’s datalog, is it possible to query for entities with an attribute that is a set of references to other entities, where all such entities satisfy some criterion? E.g.... um… all parents whose children all have red hair?


@donaldball Sure. Oh, @val_waeselynck beat me to it 🙂


@donaldball note the logical pattern here: conjunction = negation of the disjunction of the negations


I think I follow, nice, thanks.


@james remember, you don't actually need to get every bit of info from a single query, as with sql dbs


is there a good way to import data from datomic to redshift? the problem I’m solving is allowing people with sql experience to query data


I talked to Rich about it a while back and he suggested Redshift for exposing data to people who only know SQL (vs trying to write a translator from SQL->datalog)


@wei I was thinking about this issue as well. I didn't get very far writing a SQL to datalog DSL. Then I saw Stu's ETL talk and was wondering if you could just run that in reverse


possibly. need to watch that talk


I don't have any experience with Redshift though, so I was just speaking generally. it would be an interesting exercise


Any ideas how to write datomic.Entity with transit? I would like to send entity attributes to a client with transit, but now I have to manually convert it to a map before giving it to transit writer.


I know how to make custome transit/write-handler instances, but I have no idea how to write something so that the receiver can read it as a map without custome read handler.


I'm willing to admit that this might be a terrible idea...


When we are importing data, we mark the transaction entity with an import id to allow us to see which import a given datum came from. But what is the correct way to find entities with a given transaction associated with them? Everything I have come up with so far takes ages on a large base.


Tagging @marshall for when he gets back.