我有falowing table machines_hist
Contract start_time Fin_time
C1 2016-01-01 05:10:10 2016-01-01 15:10:10
C1 2016-01-02 10:16:20 2016-01-03 12:14:10
C1 2016-01-05 10:16:20 2016-01-10 17:11:10
C1 2016-02-05 02:16:20 2016-01-06 19:18:10
在一份合同上有几台机器。每台机器都有不同的开始时间和结束时间。间隔可能重叠。我必须做一份报告，该报告将显示每月合约中有多少小时的机器无法工作......
有可能吗？ 任何消化...
其他信息：该表显示了计算机的停机时间。在一个较大的表中，可能会有一列显示哪个特定机器已关闭，但这与此问题无关;我们需要按合同计算，而不是每台机器。如果有重叠，那么＆＃34;普通＆＃34;两台或多台机器之间的停机时间不应重复计算;同时关闭的两台机器与一台机器停机时的机数相同。
答案 0 :(得分：1)
设置（测试数据）：
SQL> select * from machines_hist;
CONTRACT START_TIME FIN_TIME
---------- ------------------- -------------------
C1 2015-12-30 05:10:10 2016-01-01 15:10:10
C1 2016-01-02 10:16:20 2016-01-03 12:14:10
C1 2016-01-25 10:16:20 2016-02-10 17:11:10
C1 2016-01-05 02:16:20 2016-01-06 19:18:10
C2 2016-01-15 12:20:22 2016-01-17 13:40:10
C2 2016-02-23 04:13:50 2016-02-24 02:20:44
C3 2016-02-20 10:13:20 2016-02-20 11:16:40
C4 2015-12-23 20:00:00 2015-12-24 12:23:00
C5 2015-12-31 22:34:00 2016-02-23 00:00:00
9 rows selected.
Elapsed: 00:00:00.33
查询 :(注意绑定变量 - 通常由应用程序提供）：
with a as (select to_date(:mon || '-' || :yr, 'MON-yyyy') as month_start from dual),
b as (select add_months(month_start, 1) as month_end from a),
c as (select contract, greatest(month_start, start_time) as st,
least(month_end, fin_time) as fin
from machines_hist join a on fin_time >= month_start
join b on start_time <= month_end),
m as (select contract, st,
max(fin) over (partition by contract order by st
rows between unbounded preceding and 1 preceding) as m_time
from c
union all
select contract, NULL, max(fin) from c group by contract),
n as (select contract, st, m_time
from m
where st > m_time or st is null or m_time is null),
f as (select contract, st as st_downtime,
lead(m_time) over (partition by contract order by st) as fin_downtime
from n)
select contract, max(:mon || '-' || :yr) as mth,
round(100 * sum(fin_downtime - st_downtime)/
((select month_end from b) - (select month_start from a)), 2) as downtime_pct
from f
where st_downtime is not null
group by contract
order by contract
/
绑定变量（说明SQL * Plus接口 - 每个程序都有自己的机制）：
SQL> variable yr number
SQL> variable mon varchar2(3)
SQL> begin :mon := 'JAN'; :yr := 2016; end;
2 /
PL/SQL procedure successfully completed.
Elapsed: 00:00:00.03
输出（注意：脚本保存为“downtime.sql”，通过SQL * Plus调用;本月停机时间百分比表示为22.3表示22.3％等;如果合同没有停机时间，它不包含在输出中）
SQL> start downtime
CONTRACT MTH DOWNTIME_PCT
---------- ------------ ------------
C1 JAN-2016 32.24
C2 JAN-2016 6.63
C5 JAN-2016 100
3 rows selected.
Elapsed: 00:00:00.19
答案 1 :(得分：0)
Oracle安装程序：
CREATE TABLE machines_hist ( Contract, start_time, Fin_time ) AS
SELECT 'C1', CAST( TIMESTAMP '2016-01-01 05:10:10' AS DATE ), CAST( TIMESTAMP '2016-01-01 15:10:10' AS DATE ) FROM DUAL UNION ALL
SELECT 'C1', CAST( TIMESTAMP '2016-01-02 10:16:20' AS DATE ), CAST( TIMESTAMP '2016-01-03 12:14:10' AS DATE ) FROM DUAL UNION ALL
SELECT 'C1', CAST( TIMESTAMP '2016-01-05 10:16:20' AS DATE ), CAST( TIMESTAMP '2016-01-10 17:11:10' AS DATE ) FROM DUAL UNION ALL
SELECT 'C1', CAST( TIMESTAMP '2016-01-05 02:16:20' AS DATE ), CAST( TIMESTAMP '2016-01-06 19:18:10' AS DATE ) FROM DUAL UNION ALL
SELECT 'C1', CAST( TIMESTAMP '2016-02-01 00:00:00' AS DATE ), CAST( TIMESTAMP '2016-03-01 00:00:00' AS DATE ) FROM DUAL UNION ALL
SELECT 'C1', CAST( TIMESTAMP '2016-04-01 00:00:00' AS DATE ), CAST( TIMESTAMP '2016-04-07 00:00:00' AS DATE ) FROM DUAL UNION ALL
SELECT 'C1', CAST( TIMESTAMP '2016-04-05 00:00:00' AS DATE ), CAST( TIMESTAMP '2016-04-10 00:00:00' AS DATE ) FROM DUAL;
<强>查询：
WITH times ( contract, boundary_time, type ) AS (
SELECT Contract,
Start_time,
1
FROM machines_hist
UNION ALL
SELECT Contract,
fin_time,
-1
FROM machines_hist
ORDER BY 1, 2
),
bounds ( contract, boundary_time, type, boundary_value ) AS (
SELECT t.*,
SUM( type ) OVER ( PARTITION BY Contract
ORDER BY boundary_time ASC, type DESC
ROWS BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW )
FROM times t
),
end_times ( contract, start_time, type, boundary_value, end_time ) AS (
SELECT b.*,
LEAD( CASE WHEN type = -1 AND boundary_value = 0 THEN boundary_time END )
IGNORE NULLS
OVER ( PARTITION BY Contract ORDER BY boundary_time )
AS end_time
FROM bounds b
),
filtered_end_times ( contract, start_time, end_time ) AS (
SELECT contract,
start_time,
end_time
FROM end_times
WHERE type = 1
AND boundary_value = 1
),
month_boundaries ( start_month, end_month ) AS (
SELECT TRUNC( MIN( start_time ), 'MM' ),
CASE WHEN MAX( end_time ) = TRUNC( MAX( end_time ), 'MM' )
THEN MAX( end_time )
ELSE TRUNC( MAX( end_time ), 'MM' ) + INTERVAL '1' MONTH
END
FROM filtered_end_times
),
months ( start_month, end_month ) AS (
SELECT ADD_MONTHS( start_month, LEVEL - 1),
ADD_MONTHS( start_month, LEVEL)
FROM month_boundaries
CONNECT BY ADD_MONTHS( start_month, LEVEL) <= end_month
)
SELECT contract,
start_month,
end_month
- start_month
- SUM( LEAST(end_month,end_time)-GREATEST(start_month,start_time) )
AS days_not_working
FROM months
INNER JOIN
filtered_end_times
ON ( start_time <= end_month AND end_time >= start_month )
GROUP BY
contract,
start_month,
end_month
ORDER BY
contract,
start_month
<强>输出：
CONTRACT START_MONTH DAYS_NOT_WORKING
-------- ------------------- ----------------
C1 2016-01-01 00:00:00 23.8800926
C1 2016-02-01 00:00:00 0
C1 2016-03-01 00:00:00 31
C1 2016-04-01 00:00:00 21