Clojure db使用多个参数进行准备调用
我在Clojure db使用多个参数进行准备调用,clojure,clojure-contrib,Clojure,Clojure Contrib,我在Clojure.java.jdbc (sql/db-do-prepared db "INSERT INTO fruit2 ( name, appearance, cost, grade ) VALUES ( ?, ?, ?, ? )" ["test" "test" 1 1.0]) 但是如何将下面的java代码转换成clojure。我不熟悉clojure,不知道如何传递多个vector final int numRows = 10000; PreparedStatement pstm
Clojure.java.jdbc
(sql/db-do-prepared db "INSERT INTO fruit2 ( name, appearance, cost, grade ) VALUES ( ?, ?, ?, ? )" ["test" "test" 1 1.0])
但是如何将下面的java
代码转换成clojure
。我不熟悉clojure
,不知道如何传递多个vector
final int numRows = 10000;
PreparedStatement pstmt = conn
.prepareStatement("insert into new_order values (?, ?, ?)");
for (int id = 1; id <= numRows; id++) {
pstmt.setInt(1, id % 98);
pstmt.setInt(2, id % 98);
pstmt.setInt(3, id);
int count;
if ((count = pstmt.executeUpdate()) != 1) {
System.err.println("unexpected update count for a single insert " + count);
System.exit(2);
}
if ((id % 500) == 0) {
System.out.println("Completed " + id + " inserts ...");
}
}
final int numRows=10000;
准备好的报表pstmt=conn
.prepareStatement(“插入新的订单值(?,?)”;
对于(int id=1;id对于多个向量,函数为varargs:
(sql/db-do-prepared db "INSERT INTO fruit2 ( name, appearance, cost, grade ) VALUES ( ?, ?, ?, ? )" ["test" "test" 1 1.0] ["test" "test" 2 3.0])
如果要从列表生成输入,可以使用应用:
(apply sql/db-do-prepared db "INSERT INTO fruit2 ( name, appearance, cost, grade ) VALUES ( ?, ?, ?, ? )" (for [i (range 10)] ["test" "test" i 1.0]))
对于该逻辑的文字复制,您不能使用varargs,因为它不会给您在下一个操作之前检查每个返回值的机会:
(let [num-rows 1000
success
(reduce
(fn [state id]
(let [values [(mod id 98)
(mod id 98)
id]
[result] (sql/do-prepared "insert into test values (?)" values)]
(if (not= result 1)
{:ok id}
(reduced {:error result}))))
(range 1 (inc num-rows)))]
(if-let [id (:ok success)]
(println "Completed" id "inserts")
(do (println "unexpected update count for a single insert" (:error success))
(System/exit 2))))
在我的例子中,我认为@noisesmith是正确的,但我认为sql参数应该在集合(vector)中
(sql/db-do准备好了吗
分贝
[“在FROUT2中插入(名称、外观、成本、等级)值(?,?,?)”
“测试”“测试”1.0])
我认为这对我很有用(我是否遗漏了什么请告诉我)
或者API自2013年以来发生了变化对不起,我不明白你的问题。请你详细说明一下好吗?