小编Ora*_*key的帖子

Java 8 Streams:获得非重复计数

这是输入和输出的SQL版本:

     with tab1 as (

        select 1 as id from dual union all
        select 1 as id from dual union all
        select 2 as id from dual union all
        select 2 as id from dual union all
        select 5 as id from dual 
        )

    select id from tab1 group by id having count(id)=1;

Output is Id=5 and count is 1
Run Code Online (Sandbox Code Playgroud)

因为5不重复.我如何使用JAVA 8流实现它?

我试过下面,但很明显它给出了错误的结果

List<Integer> myList = new ArrayList<Integer>();
                myList.add(1);
                myList.add(1);
                myList.add(2);
                myList.add(2);
                myList.add(5);

                Long f =  myList.stream()
                          .distinct().count();

                System.out.println(f);
Run Code Online (Sandbox Code Playgroud)

java java-8 java-stream

6
推荐指数
1
解决办法
119
查看次数

标签 统计

java ×1

java-8 ×1

java-stream ×1