使用 WITH AS 后获取重复记录

Question

我有三个选择查询，它们按小时对月份最后一天（当前、当前-1、当前-2）的记录进行计数。

我正在尝试使其三个输出并排出现的单个查询。

我使用with as 来完成这项工作。

问题是获得重复记录（近 2k 条记录），其中预期的最大行数为 24（因为每天 24 小时）。

查询：

with curr as 
(
  Select
    last_day(add_months(trunc(sysdate, 'mm'), 0)),
    TO_CHAR(created_date, 'HH24') as "Time",
    count(1) as "Count"
  from
    table1
  where cretd_date >= trunc(last_day(add_months(trunc(sysdate, 'mm'), 0)))
  group by
    TO_CHAR(created_date, 'HH24'),
    last_day(add_months(trunc(sysdate, 'mm'), 0))
  order by
    TO_CHAR(cretd_date, 'HH24')
),
curr_1 as 
(
  Select
    last_day(add_months(trunc(sysdate, 'mm'), -1)),
    TO_CHAR(created_date, 'HH24') as "Time",
    count(1) as "Count"
  from
    table1
  where cretd_date >= trunc(last_day(add_months(trunc(sysdate, 'mm'), -1)))
  group by
    TO_CHAR(created_date, 'HH24'),
    last_day(add_months(trunc(sysdate, 'mm'), -1))
  order by
    TO_CHAR(cretd_date, 'HH24')
),
curr_2 as
(
  Select
    last_day(add_months(trunc(sysdate, 'mm'), -2)),
    TO_CHAR(created_date, 'HH24') as "Time",
    count(1) as "Count"
  from
    table1
  where cretd_date >= trunc(last_day(add_months(trunc(sysdate, 'mm'), -2)))
  group by
    TO_CHAR(created_date, 'HH24'),
    last_day(add_months(trunc(sysdate, 'mm'), -2))
  order by
    TO_CHAR(cretd_date, 'HH24')
)
select * from curr, curr_1,curr_2;

实际输出：

2k repeated rows

预期输出：

max 24 rows

last_date  | time   | count   | last_date  | time_1 | count_1 | last_date | time_2| count_2 |
31-july-19 | 00     | 2       | 31-June-19 | 00     | 1       | 31-May-19 | 00    | 3       |
...
31-july-19 | 23     | 34      | 31-June-19 | 23     | 23      | 31-May-19 | 23    | 32      | 

* 如果有任何其他最佳方法可以实现相同的效果，请分享。

Answer 1

我想您想对每月结果进行透视，您可以使用条件聚合。

SELECT TO_CHAR(created_date, 'HH24') AS "Time"
    ,last_day(sysdate) AS m1
    ,last_day(add_months(sysdate, - 1)) m2
    ,last_day(add_months(sysdate, - 2)) m3
    ,count(CASE 
            WHEN created_date >= trunc(last_day(sysdate))
                THEN 1
            END) m1_count
    ,count(CASE 
            WHEN created_date >= trunc(last_day(add_months(sysdate, - 1)))
                THEN 1
            END) m2_count
    ,count(CASE 
            WHEN created_date >= trunc(last_day(add_months(sysdate, - 2)))
                THEN 1
            END) m3_count
FROM table1
GROUP BY TO_CHAR(created_date, 'HH24')
ORDER BY "Time";

注意：由于您尚未提供数据，因此这是未经测试的查询。请尝试告诉我。

Answer 2

您缺少CURR, CURR_1, CURR_2 之间的连接。

加入应该基于列"Time"。

所以你的SELECT 查询应该是这样的：

SELECT
    *
FROM
    CURR JOIN
    CURR_1 USING("Time") JOIN
    CURR_2 USING("Time");

干杯！！