It seems that datomic.api/delete-db does not free up the disk space. Does the API support freeing up the disk space, or do I need to delete the db directory by hand?

@grav What storage are you using? You’re correct that delete-db does not reclaim the disk space. You need to run gc-deleted-dbs : http://docs.datomic.com/capacity.html#storage-size (very bottom) Then depending on your storage you’ll need to run compaction/vacuum/etc

Generally if you’re not in production it is easier to backup, delete the table entirely, recreate and restore

The other thing to keep in mind about disk space usage is that you need to run gcStorage periodically http://docs.datomic.com/capacity.html#garbage-collection on live databases to remove garbage segments

remember to use get-database-list to see what other dbs you have. i’ve deleted the http://www.stuttaford.me/codex database more than once doing that 😞

Anyone aware of a predicate that’ll return true for ordinary maps and EntityMaps, but not for vectors?

(map? my-entity-map) is false; (associative? vector) is true.

I can create a custom pred, of course, but I hate to do that on something intended as a general-purpose fn.

#(instance? clojure.lang.ILookup %) will tell you whether it can do keyword lookup

Ooh, very nice.

if that’s not exactly what you need, I would consider writing a predicate that describes exactly the traits you expect to use rather than trying to figure out some common parent

(as there likely isn’t one)

No, keyword lookup was exactly what I was after. Thanks @alexmiller!

map? corresponds to IPersistentMap (which implies things like persistence)

associative? corresponds to Associative which is more about being able to look up val by key

Ah, and since you can look up items in vectors by index...

yeah

if you have a datomic entity in hand, you can also look at what it implements with (supers (class entity))

Cool, wasn't aware of that one, thanks!

kind of interesting to compare across different types

there’s also some interesting class diagrams out there

Yeah, I'm going to end up doing that just to satisfy some curiosity 🙂

https://github.com/Chouser/clojure-classes/tree/master

and Stuart has something similar somewhere

Cool!

https://github.com/stuartsierra/class-diagram

I found the latter particularly helpful before I had internalized a lot of that stuff

My new wallpaper 😉

Where can I find docs for older versions of datomic? Looking specifically for 0.9.5344