(ns db-example
(:use [clojure.contrib.sql :only (with-connection with-query-results)] )
(:import (java.sql DriverManager)))
;; need this to load the sqlite3 driver (as a side effect of evaluating the expression)
(Class/forName "org.sqlite.JDBC")
(def +db-path+ "...")
(def +db-specs+ {:classname "org.sqlite.JDBC",:subprotocol "sqlite",:subname +db-path+})
(def +transactions-query+ "select * from my_table")
(with-connection +db-specs+
(with-query-results results [+transactions-query+]
;; results is an array of column_name -> value maps
))
你必须从with-query-results宏中实际返回一些东西.因为seq绑定到结果是懒惰的,让我们消耗它：
(with-connection +db-specs+
(with-query-results results [+transactions-query+]
(doall results)))
这是使用clojure.contrib.sql时的常见模式,不依赖于sqlite JDBC适配器.
顺便说一句,我从来没有必须手动执行(Class / forName driver-class-str),这显然是你的Java习惯.驱动程序被加载到contrib.sql的引擎盖下.
