有没有一个规范的方法来抓住所有的idents从一个特定的数据分区？ [英] is there a canonical way to grab all idents from a particular datomic partition?

问题描述

说我有作为数据库模式安装的：user / name 和：user / gender

say I had :user/name and :user/gender installed as datomic schema.

(pprint (d/q '[:find ?ident :where
               [?e :db/ident ?ident]
               [_ :db.install/attribute ?e]] (d/db conn)))

查找所有db.install / attributes

finds all the db.install/attributes

 #{[:db/code] [:user/gender] [:fressian/tag] [:db/unique] [:user/name] [:db/fn] 
 [:db/noHistory] [:db/fulltext] [:db/lang] [:db/valueType] [:db/doc]
 [:db/isComponent] [:db.install/function] [:db/cardinality] [:db/txInstant] [:db/index]}

但是，我只想列出以下项目：user namespace

however, I only want to list items in the :user namespace

[:user/gender] [:user/name]

推荐答案

我想出来了

(d/q '[:find ?ident :where
           [?e :db/ident ?ident]
           [_ :db.install/attribute ?e]
           [(.toString ?ident) ?val]
           [(.startsWith ?val ":user")]] (d/db *conn*))

;; => #{[:user/gender] [:user/firstName]}

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