聚合计数窗口函数

Question

我正在尝试进行返回具有相同名称的行的查询。

查询

SELECT
 version,
 name,
 count (version) OVER (PARTITION BY name)
FROM
 application
WHERE id = 123;

我明白了：

 version |         name         | count 
---------+----------------------+-------
 29.0    | Mouser               |     2
 28.0    | Mouser               |     2
 11.0    | Niche Norman         |     1
         | Galaxy Creator       |     0
         | Cube Generator       |     0

虽然预期的结果是：

 version |         name         | count 
---------+----------------------+-------
 29.0    | Mouser               |     2
 28.0    | Mouser               |     2

但是当我使用having count > 1 时，它什么也没有返回。

Answer 1

您不能将 HAVING 与窗口聚合一起使用：

SELECT *
FROM
 (
    SELECT
     version,
     name,
     count (version) OVER (PARTITION BY name) as cnt
    FROM
     application
    WHERE id = 123
 ) as dt
WHERE cnt > 2;