clojure - Korma中 `oracle`函数的具体用法和clojure代码的含义？

Question

我正在尝试使用 Korma 连接到 Oracle 数据库。首先我尝试使用此代码并成功连接。

(defdb korma-db
  {:classname "oracle.jdbc.OracleDriver"
   :subprotocol "oracle"
   :subname "thin:@my.oracle.db:1521:testdb"
   :user "xxx"
   :password "xxx"
   :naming {:keys str/lower-case :fields str/upper-case}})

但是我发现还有一个更方便的函数korma.db.oracle。所以代码看起来像这样简化:

(defdb korma-db
  (oracle {:keys ["my.oracle.db" 1521 true]
           :as {:user "xxx" :password "xxx"}
           :naming {:keys str/lower-case :fields str/upper-case}}))

但是失败了。它尝试访问 localhost。当我检查oracle 函数的结果时，我发现有些奇怪。

{:naming {:keys #<string$lower_case clojure.string$lower_case@5ba760ac>,
 :fields #<string$upper_case clojure.string$upper_case@504f4c0b>},
 :as {:user "xxx", :password "xxx"},
 :keys ["my.oracle.db" 1521 true],
 :classname "oracle.jdbc.driver.OracleDriver",
 :subprotocol "oracle:thin",
 :subname "@localhost:1521", :make-pool? true}
            ^^^^^^^^^

我查看了Korma源码，oracle函数的代码是:

(defn oracle
  "Create a database specification for an Oracle database. Opts should include keys
  for :user and :password. You can also optionally set host and port."
  [{:keys [host port make-pool?]
    :or {host "localhost", port 1521, make-pool? true}
    :as opts}]
  (merge {:classname "oracle.jdbc.driver.OracleDriver" ; must be in classpath
          :subprotocol "oracle:thin"
          :subname (str "@" host ":" port)
          :make-pool? make-pool?}
         opts))

简而言之，我的问题是:

• oracle函数的具体用法是什么？我错过了什么？
• oracle 函数的代码对我来说看起来很奇怪。谁能解释一下请提供代码，尤其是参数部分...[{:keys [host ....] :or {...} :as ...}]

Answer 1

这个 oracle 函数 destructuring its arguments .这是一个 article about this feature .

所以，调用oracle的正确方法是:

(defdb korma-db
  (oracle { :user "xxx"
            :password "xxx"
            :host "my.oracle.db"
            :port 1521
            :make-pool? true }))

编辑:可以像这样指定 oracle SID:

(defdb korma-db
  (oracle {:subname "@//xxx.xxx.xxx.xxx:1521/testdb"
           :user "xxx"
           :password "xxx"
           :naming {:keys str/lower-case :fields str/upper-case}}))