Sum 在 postgres 中不起作用。 （从 mysql 语法切换到 postgres）
Sum is not working in postgres. (Switching from mysql syntax to postgres)
我在 Mysql 中有这个，它工作得很好。将我的项目从 mysql 切换到 postgres:
SELECT
CASE
WHEN EXTRACT(HOUR FROM t_stamp) >= 5 AND EXTRACT(HOUR FROM t_stamp) < 6 THEN '5-6'
WHEN EXTRACT(HOUR FROM t_stamp) >= 6 AND EXTRACT(HOUR FROM t_stamp) < 7 THEN '6-7'
WHEN EXTRACT(HOUR FROM t_stamp) >= 7 AND EXTRACT(HOUR FROM t_stamp) < 8 THEN '7-8'
WHEN EXTRACT(HOUR FROM t_stamp) >= 8 AND EXTRACT(HOUR FROM t_stamp) < 9 THEN '8-9'
WHEN EXTRACT(HOUR FROM t_stamp) >= 9 AND EXTRACT(HOUR FROM t_stamp) < 10 THEN '9-10'
WHEN EXTRACT(HOUR FROM t_stamp) >= 10 AND EXTRACT(HOUR FROM t_stamp) < 11 THEN '10-11'
WHEN EXTRACT(HOUR FROM t_stamp) >= 11 AND EXTRACT(HOUR FROM t_stamp) < 12 THEN '11-12'
WHEN EXTRACT(HOUR FROM t_stamp) >= 12 AND EXTRACT(HOUR FROM t_stamp) < 13 THEN '12-13'
WHEN EXTRACT(HOUR FROM t_stamp) >= 13 AND EXTRACT(HOUR FROM t_stamp) < 14 THEN '13-14'
WHEN EXTRACT(HOUR FROM t_stamp) >= 14 AND EXTRACT(HOUR FROM t_stamp) < 15 THEN '14-15'
WHEN EXTRACT(HOUR FROM t_stamp) >= 15 AND EXTRACT(HOUR FROM t_stamp) < 16 THEN '14-15'
WHEN EXTRACT(HOUR FROM t_stamp) >= 16 AND EXTRACT(HOUR FROM t_stamp) < 17 THEN '14-15'
WHEN EXTRACT(HOUR FROM t_stamp) >= 17 AND EXTRACT(HOUR FROM t_stamp) < 18 THEN '14-15'
WHEN EXTRACT(HOUR FROM t_stamp) >= 18 AND EXTRACT(HOUR FROM t_stamp) < 19 THEN '14-15'
WHEN EXTRACT(HOUR FROM t_stamp) >= 19 AND EXTRACT(HOUR FROM t_stamp) < 20 THEN '14-15'
WHEN EXTRACT(HOUR FROM t_stamp) >= 20 AND EXTRACT(HOUR FROM t_stamp) < 21 THEN '14-15'
WHEN EXTRACT(HOUR FROM t_stamp) >= 21 AND EXTRACT(HOUR FROM t_stamp) < 22 THEN '14-15'
WHEN EXTRACT(HOUR FROM t_stamp) >= 22 AND EXTRACT(HOUR FROM t_stamp) < 23 THEN '14-15'
WHEN EXTRACT(HOUR FROM t_stamp) >= 23 AND EXTRACT(HOUR FROM t_stamp) < 24 THEN '14-15'
WHEN EXTRACT(HOUR FROM t_stamp) >= 24 AND EXTRACT(HOUR FROM t_stamp) < 0 THEN '14-15'
WHEN EXTRACT(HOUR FROM t_stamp) >= 0 AND EXTRACT(HOUR FROM t_stamp) < 1 THEN '14-15'
WHEN EXTRACT(HOUR FROM t_stamp) >= 1 AND EXTRACT(HOUR FROM t_stamp) < 2 THEN '14-15'
WHEN EXTRACT(HOUR FROM t_stamp) >= 2 AND EXTRACT(HOUR FROM t_stamp) < 3 THEN '14-15'
WHEN EXTRACT(HOUR FROM t_stamp) >= 3 AND EXTRACT(HOUR FROM t_stamp) < 4 THEN '14-15'
WHEN EXTRACT(HOUR FROM t_stamp) >= 4 AND EXTRACT(HOUR FROM t_stamp) < 5 THEN '14-15'
END as onehour,
CASE
WHEN EXTRACT(HOUR FROM t_stamp) >= 5 AND EXTRACT(HOUR FROM t_stamp) < 6 THEN sum(case when "FullSheetNumber" != 0 then 1 else 0 end)
WHEN EXTRACT(HOUR FROM t_stamp) >= 6 AND EXTRACT(HOUR FROM t_stamp) < 7 THEN sum(case when "FullSheetNumber" != 0 then 1 else 0 end)
WHEN EXTRACT(HOUR FROM t_stamp) >= 7 AND EXTRACT(HOUR FROM t_stamp) < 8 THEN sum(case when "FullSheetNumber" != 0 then 1 else 0 end)
WHEN EXTRACT(HOUR FROM t_stamp) >= 8 AND EXTRACT(HOUR FROM t_stamp) < 9 THEN sum(case when "FullSheetNumber" != 0 then 1 else 0 end)
WHEN EXTRACT(HOUR FROM t_stamp) >= 9 AND EXTRACT(HOUR FROM t_stamp) < 10 THEN sum(case when "FullSheetNumber" != 0 then 1 else 0 end)
WHEN EXTRACT(HOUR FROM t_stamp) >= 10 AND EXTRACT(HOUR FROM t_stamp) < 11 THEN sum(case when "FullSheetNumber" != 0 then 1 else 0 end)
WHEN EXTRACT(HOUR FROM t_stamp) >= 11 AND EXTRACT(HOUR FROM t_stamp) < 12 THEN sum(case when "FullSheetNumber" != 0 then 1 else 0 end)
WHEN EXTRACT(HOUR FROM t_stamp) >= 12 AND EXTRACT(HOUR FROM t_stamp) < 13 THEN sum(case when "FullSheetNumber" != 0 then 1 else 0 end)
WHEN EXTRACT(HOUR FROM t_stamp) >= 13 AND EXTRACT(HOUR FROM t_stamp) < 14 THEN sum(case when "FullSheetNumber" != 0 then 1 else 0 end)
WHEN EXTRACT(HOUR FROM t_stamp) >= 14 AND EXTRACT(HOUR FROM t_stamp) < 15 THEN sum(case when "FullSheetNumber" != 0 then 1 else 0 end)
WHEN EXTRACT(HOUR FROM t_stamp) >= 15 AND EXTRACT(HOUR FROM t_stamp) < 16 THEN sum(case when "FullSheetNumber" != 0 then 1 else 0 end)
WHEN EXTRACT(HOUR FROM t_stamp) >= 16 AND EXTRACT(HOUR FROM t_stamp) < 17 THEN sum(case when "FullSheetNumber" != 0 then 1 else 0 end)
WHEN EXTRACT(HOUR FROM t_stamp) >=17 AND EXTRACT(HOUR FROM t_stamp) < 18 THEN sum(case when "FullSheetNumber" != 0 then 1 else 0 end)
WHEN EXTRACT(HOUR FROM t_stamp) >= 18 AND EXTRACT(HOUR FROM t_stamp) < 19 THEN sum(case when "FullSheetNumber" != 0 then 1 else 0 end)
WHEN EXTRACT(HOUR FROM t_stamp) >= 19 AND EXTRACT(HOUR FROM t_stamp) < 20 THEN sum(case when "FullSheetNumber" != 0 then 1 else 0 end)
WHEN EXTRACT(HOUR FROM t_stamp) >= 20 AND EXTRACT(HOUR FROM t_stamp) < 21 THEN sum(case when "FullSheetNumber" != 0 then 1 else 0 end)
WHEN EXTRACT(HOUR FROM t_stamp) >= 21 AND EXTRACT(HOUR FROM t_stamp) < 22 THEN sum(case when "FullSheetNumber" != 0 then 1 else 0 end)
WHEN EXTRACT(HOUR FROM t_stamp) >= 22 AND EXTRACT(HOUR FROM t_stamp) < 23 THEN sum(case when "FullSheetNumber" != 0 then 1 else 0 end)
WHEN EXTRACT(HOUR FROM t_stamp) >= 23 AND EXTRACT(HOUR FROM t_stamp) < 24 THEN sum(case when "FullSheetNumber" != 0 then 1 else 0 end)
WHEN EXTRACT(HOUR FROM t_stamp) >= 24 AND EXTRACT(HOUR FROM t_stamp) < 0 THEN sum(case when "FullSheetNumber" != 0 then 1 else 0 end)
WHEN EXTRACT(HOUR FROM t_stamp) >= 0 AND EXTRACT(HOUR FROM t_stamp) < 1 THEN sum(case when "FullSheetNumber" != 0 then 1 else 0 end)
WHEN EXTRACT(HOUR FROM t_stamp) >= 1 AND EXTRACT(HOUR FROM t_stamp) < 2 THEN sum(case when "FullSheetNumber" != 0 then 1 else 0 end)
WHEN EXTRACT(HOUR FROM t_stamp) >= 2 AND EXTRACT(HOUR FROM t_stamp) < 3 THEN sum(case when "FullSheetNumber" != 0 then 1 else 0 end)
WHEN EXTRACT(HOUR FROM t_stamp) >= 3 AND EXTRACT(HOUR FROM t_stamp) < 4 THEN sum(case when "FullSheetNumber" != 0 then 1 else 0 end)
WHEN EXTRACT(HOUR FROM t_stamp) >= 4 AND EXTRACT(HOUR FROM t_stamp) < 5 THEN sum(case when "FullSheetNumber" != 0 then 1 else 0 end)
END as total_eachhour
FROM group_table
GROUP BY onehour,t_stamp
ORDER BY onehour
和当前结果：
enter image description here
但我真正想要的是：
onehour
total_eachhour
10-11
56
11-12
32
你的根本问题是：GROUP BY onehour,t_stamp 它应该只是 GROUP BY onehour
但是，您的查询可以简化。您不需要 count() 的 case 表达式，我会使用适当的 time 值来定义小时范围：
条件聚合可以在 Postgres 中使用 filter() 完成，我认为它更具可读性：
因此查询将如下所示：
select case
when t_stamp::time >= '05:00' and t_stamp::time < '06:00' then '5-6'
when t_stamp::time >= '06:00' and t_stamp::time < '07:00' then '6-7'
when t_stamp::time >= '07:00' and t_stamp::time < '08:00' then '7-8'
when t_stamp::time >= '08:00' and t_stamp::time < '09:00' then '8-9'
when t_stamp::time >= '09:00' and t_stamp::time < '10:00' then '9-10'
....
end as one_our,
count(*) filter (where "FullSheetNumber" <> 0 ) as total_eachhour
from group_table
group by one_our;
我在 Mysql 中有这个，它工作得很好。将我的项目从 mysql 切换到 postgres:
SELECT
CASE
WHEN EXTRACT(HOUR FROM t_stamp) >= 5 AND EXTRACT(HOUR FROM t_stamp) < 6 THEN '5-6'
WHEN EXTRACT(HOUR FROM t_stamp) >= 6 AND EXTRACT(HOUR FROM t_stamp) < 7 THEN '6-7'
WHEN EXTRACT(HOUR FROM t_stamp) >= 7 AND EXTRACT(HOUR FROM t_stamp) < 8 THEN '7-8'
WHEN EXTRACT(HOUR FROM t_stamp) >= 8 AND EXTRACT(HOUR FROM t_stamp) < 9 THEN '8-9'
WHEN EXTRACT(HOUR FROM t_stamp) >= 9 AND EXTRACT(HOUR FROM t_stamp) < 10 THEN '9-10'
WHEN EXTRACT(HOUR FROM t_stamp) >= 10 AND EXTRACT(HOUR FROM t_stamp) < 11 THEN '10-11'
WHEN EXTRACT(HOUR FROM t_stamp) >= 11 AND EXTRACT(HOUR FROM t_stamp) < 12 THEN '11-12'
WHEN EXTRACT(HOUR FROM t_stamp) >= 12 AND EXTRACT(HOUR FROM t_stamp) < 13 THEN '12-13'
WHEN EXTRACT(HOUR FROM t_stamp) >= 13 AND EXTRACT(HOUR FROM t_stamp) < 14 THEN '13-14'
WHEN EXTRACT(HOUR FROM t_stamp) >= 14 AND EXTRACT(HOUR FROM t_stamp) < 15 THEN '14-15'
WHEN EXTRACT(HOUR FROM t_stamp) >= 15 AND EXTRACT(HOUR FROM t_stamp) < 16 THEN '14-15'
WHEN EXTRACT(HOUR FROM t_stamp) >= 16 AND EXTRACT(HOUR FROM t_stamp) < 17 THEN '14-15'
WHEN EXTRACT(HOUR FROM t_stamp) >= 17 AND EXTRACT(HOUR FROM t_stamp) < 18 THEN '14-15'
WHEN EXTRACT(HOUR FROM t_stamp) >= 18 AND EXTRACT(HOUR FROM t_stamp) < 19 THEN '14-15'
WHEN EXTRACT(HOUR FROM t_stamp) >= 19 AND EXTRACT(HOUR FROM t_stamp) < 20 THEN '14-15'
WHEN EXTRACT(HOUR FROM t_stamp) >= 20 AND EXTRACT(HOUR FROM t_stamp) < 21 THEN '14-15'
WHEN EXTRACT(HOUR FROM t_stamp) >= 21 AND EXTRACT(HOUR FROM t_stamp) < 22 THEN '14-15'
WHEN EXTRACT(HOUR FROM t_stamp) >= 22 AND EXTRACT(HOUR FROM t_stamp) < 23 THEN '14-15'
WHEN EXTRACT(HOUR FROM t_stamp) >= 23 AND EXTRACT(HOUR FROM t_stamp) < 24 THEN '14-15'
WHEN EXTRACT(HOUR FROM t_stamp) >= 24 AND EXTRACT(HOUR FROM t_stamp) < 0 THEN '14-15'
WHEN EXTRACT(HOUR FROM t_stamp) >= 0 AND EXTRACT(HOUR FROM t_stamp) < 1 THEN '14-15'
WHEN EXTRACT(HOUR FROM t_stamp) >= 1 AND EXTRACT(HOUR FROM t_stamp) < 2 THEN '14-15'
WHEN EXTRACT(HOUR FROM t_stamp) >= 2 AND EXTRACT(HOUR FROM t_stamp) < 3 THEN '14-15'
WHEN EXTRACT(HOUR FROM t_stamp) >= 3 AND EXTRACT(HOUR FROM t_stamp) < 4 THEN '14-15'
WHEN EXTRACT(HOUR FROM t_stamp) >= 4 AND EXTRACT(HOUR FROM t_stamp) < 5 THEN '14-15'
END as onehour,
CASE
WHEN EXTRACT(HOUR FROM t_stamp) >= 5 AND EXTRACT(HOUR FROM t_stamp) < 6 THEN sum(case when "FullSheetNumber" != 0 then 1 else 0 end)
WHEN EXTRACT(HOUR FROM t_stamp) >= 6 AND EXTRACT(HOUR FROM t_stamp) < 7 THEN sum(case when "FullSheetNumber" != 0 then 1 else 0 end)
WHEN EXTRACT(HOUR FROM t_stamp) >= 7 AND EXTRACT(HOUR FROM t_stamp) < 8 THEN sum(case when "FullSheetNumber" != 0 then 1 else 0 end)
WHEN EXTRACT(HOUR FROM t_stamp) >= 8 AND EXTRACT(HOUR FROM t_stamp) < 9 THEN sum(case when "FullSheetNumber" != 0 then 1 else 0 end)
WHEN EXTRACT(HOUR FROM t_stamp) >= 9 AND EXTRACT(HOUR FROM t_stamp) < 10 THEN sum(case when "FullSheetNumber" != 0 then 1 else 0 end)
WHEN EXTRACT(HOUR FROM t_stamp) >= 10 AND EXTRACT(HOUR FROM t_stamp) < 11 THEN sum(case when "FullSheetNumber" != 0 then 1 else 0 end)
WHEN EXTRACT(HOUR FROM t_stamp) >= 11 AND EXTRACT(HOUR FROM t_stamp) < 12 THEN sum(case when "FullSheetNumber" != 0 then 1 else 0 end)
WHEN EXTRACT(HOUR FROM t_stamp) >= 12 AND EXTRACT(HOUR FROM t_stamp) < 13 THEN sum(case when "FullSheetNumber" != 0 then 1 else 0 end)
WHEN EXTRACT(HOUR FROM t_stamp) >= 13 AND EXTRACT(HOUR FROM t_stamp) < 14 THEN sum(case when "FullSheetNumber" != 0 then 1 else 0 end)
WHEN EXTRACT(HOUR FROM t_stamp) >= 14 AND EXTRACT(HOUR FROM t_stamp) < 15 THEN sum(case when "FullSheetNumber" != 0 then 1 else 0 end)
WHEN EXTRACT(HOUR FROM t_stamp) >= 15 AND EXTRACT(HOUR FROM t_stamp) < 16 THEN sum(case when "FullSheetNumber" != 0 then 1 else 0 end)
WHEN EXTRACT(HOUR FROM t_stamp) >= 16 AND EXTRACT(HOUR FROM t_stamp) < 17 THEN sum(case when "FullSheetNumber" != 0 then 1 else 0 end)
WHEN EXTRACT(HOUR FROM t_stamp) >=17 AND EXTRACT(HOUR FROM t_stamp) < 18 THEN sum(case when "FullSheetNumber" != 0 then 1 else 0 end)
WHEN EXTRACT(HOUR FROM t_stamp) >= 18 AND EXTRACT(HOUR FROM t_stamp) < 19 THEN sum(case when "FullSheetNumber" != 0 then 1 else 0 end)
WHEN EXTRACT(HOUR FROM t_stamp) >= 19 AND EXTRACT(HOUR FROM t_stamp) < 20 THEN sum(case when "FullSheetNumber" != 0 then 1 else 0 end)
WHEN EXTRACT(HOUR FROM t_stamp) >= 20 AND EXTRACT(HOUR FROM t_stamp) < 21 THEN sum(case when "FullSheetNumber" != 0 then 1 else 0 end)
WHEN EXTRACT(HOUR FROM t_stamp) >= 21 AND EXTRACT(HOUR FROM t_stamp) < 22 THEN sum(case when "FullSheetNumber" != 0 then 1 else 0 end)
WHEN EXTRACT(HOUR FROM t_stamp) >= 22 AND EXTRACT(HOUR FROM t_stamp) < 23 THEN sum(case when "FullSheetNumber" != 0 then 1 else 0 end)
WHEN EXTRACT(HOUR FROM t_stamp) >= 23 AND EXTRACT(HOUR FROM t_stamp) < 24 THEN sum(case when "FullSheetNumber" != 0 then 1 else 0 end)
WHEN EXTRACT(HOUR FROM t_stamp) >= 24 AND EXTRACT(HOUR FROM t_stamp) < 0 THEN sum(case when "FullSheetNumber" != 0 then 1 else 0 end)
WHEN EXTRACT(HOUR FROM t_stamp) >= 0 AND EXTRACT(HOUR FROM t_stamp) < 1 THEN sum(case when "FullSheetNumber" != 0 then 1 else 0 end)
WHEN EXTRACT(HOUR FROM t_stamp) >= 1 AND EXTRACT(HOUR FROM t_stamp) < 2 THEN sum(case when "FullSheetNumber" != 0 then 1 else 0 end)
WHEN EXTRACT(HOUR FROM t_stamp) >= 2 AND EXTRACT(HOUR FROM t_stamp) < 3 THEN sum(case when "FullSheetNumber" != 0 then 1 else 0 end)
WHEN EXTRACT(HOUR FROM t_stamp) >= 3 AND EXTRACT(HOUR FROM t_stamp) < 4 THEN sum(case when "FullSheetNumber" != 0 then 1 else 0 end)
WHEN EXTRACT(HOUR FROM t_stamp) >= 4 AND EXTRACT(HOUR FROM t_stamp) < 5 THEN sum(case when "FullSheetNumber" != 0 then 1 else 0 end)
END as total_eachhour
FROM group_table
GROUP BY onehour,t_stamp
ORDER BY onehour
和当前结果： enter image description here
但我真正想要的是：
| onehour | total_eachhour |
|---|---|
| 10-11 | 56 |
| 11-12 | 32 |
你的根本问题是：GROUP BY onehour,t_stamp 它应该只是 GROUP BY onehour
但是，您的查询可以简化。您不需要 count() 的 case 表达式，我会使用适当的 time 值来定义小时范围：
条件聚合可以在 Postgres 中使用 filter() 完成，我认为它更具可读性：
因此查询将如下所示：
select case
when t_stamp::time >= '05:00' and t_stamp::time < '06:00' then '5-6'
when t_stamp::time >= '06:00' and t_stamp::time < '07:00' then '6-7'
when t_stamp::time >= '07:00' and t_stamp::time < '08:00' then '7-8'
when t_stamp::time >= '08:00' and t_stamp::time < '09:00' then '8-9'
when t_stamp::time >= '09:00' and t_stamp::time < '10:00' then '9-10'
....
end as one_our,
count(*) filter (where "FullSheetNumber" <> 0 ) as total_eachhour
from group_table
group by one_our;