SQL：按日期分组并汇总列中的值

Question

我有一个JDBC数据库（特别是DB2，但我正在寻找与DB无关的数据库，至少是DB2和Oracle），该数据库的表每隔10分钟就会插入一条记录，记录中包含有关该应用程序运行的API的统计信息。 看起来像：

StatKey, StartDate, EndDate, APIName, StatName, StatValue
201505071498224437562706    2015-05-07 14:12:44.0   2015-05-07 14:22:44.0   API5    Invocations 34
201505071498161437466684    2015-05-07 14:06:14.0   2015-05-07 14:16:14.0   API4    Invocations 79
201505071498060937466556    2015-05-07 13:56:08.0   2015-05-07 14:06:08.0   API4    Average 26,264.37
201505071497263437627286    2015-05-07 14:16:33.0   2015-05-07 14:26:34.0   API2    Invocations 24
201505071497262137620812    2015-05-07 14:16:19.0   2015-05-07 14:26:20.0   API2    Invocations 24
201505071497024537466378    2015-05-07 13:52:43.0   2015-05-07 14:02:44.0   API1    Average 6,830,050
201505071497023337466368    2015-05-07 13:52:31.0   2015-05-07 14:02:32.0   API3    Average 31,523
201505071496023337466361    2015-05-07 13:52:31.0   2015-05-07 14:02:32.0   API2    Invocations 1
201505071494263837628892    2015-05-07 14:16:36.0   2015-05-07 14:26:37.0   API5    Invocations 68
201505071493124437466656    2015-05-07 14:02:44.0   2015-05-07 14:12:44.0   API1    Invocations 2
201505071492263037625304    2015-05-07 14:16:29.0   2015-05-07 14:26:30.0   API3    Average 179,223.29

每隔10分钟，在此期间执行的任何API都会具有与上述类似的条目。 但是，多个JVM将写入同一数据库，因此开始和结束时间不只是每10分钟一次，而且每小时可能有6个以上的条目。

我要尝试做的是创建一个SQL，该SQL将每小时运行时间的所有API的所有调用分组。 例如：

Date&Hour, API, Invocations
2015-05-07 12:00, API1, 100
2015-05-07 12:00, API2, 150
2015-05-07 13:00, API2, 200
etc...

我尝试在小时标记的主键（始终是时间戳加上一些随机数字-但小时和分钟之间是2个随机数字）的SUBSTR进行GROUP BY，但我不确定如何每小时添加所有StatName = Invocations。

有人可以提供一些有关如何实现此目标的想法吗？

Answer 1

不太确定这是什么吗？

本质上，它查看YYYYMMDDHH 10个位置，因为它们包含要分组的值...然后仅基于调用求和

SELECT substr(statKey,1,10) as DH, APIName, Sum(Statvalue) Invocations
FROM TableName
WHERE StatName = 'Invocations'
GROUP BY substr(statKey,1,10), APIName, StatName

例：

WITH CTE AS
  (SELECT '201505071498224437562706' AS StatKey,
    '2015-05-07 14:12:44.0'          AS StartDate,
    '2015-05-07 14:22:44.0'          AS EndDate,
    'API5'                           AS APIName,
    'Invocations'                    AS StatName,
    34                               AS statvalue
  FROM dual
  UNION ALL
  SELECT '201505071498161437466684',
    '2015-05-07 14:06:14.0',
    '2015-05-07 14:16:14.0',
    'API4',
    'Invocations',
    79
  FROM dual
  UNION ALL
  SELECT '201505071498060937466556',
    '2015-05-07 13:56:08.0',
    '2015-05-07 14:06:08.0',
    'API4',
    'Average',
    26264.37
  FROM dual
  )
SELECT substr(statKey,1,10) as DH, APIName, StatName, Sum(Statvalue) 
FROM TableName
WHERE StatName = 'Invocations'
GROUP BY substr(statKey,1,10), APIName, StatName

Answer 2

至少对于DB2，为什么不只是

select date(startdate) as start_date
       , hour(startdate) as start_hour
       , API
       , sum(statvalue) as Invocations
from mytbl
where statname = 'Invocations' 
group by date(startdate),  hour(startdate), API

如果您确实要这么做，我将把它留作练习，让您将日期和小时组合回时间戳中。

Answer 3

另一个可能的解决方案：

select to_char(StarDate,'rrrr-mm-dd HH24:')||'00'  as DateHour,
    APIName as API,
    sum(StatValue) as Invocations
from STATISTICS
where StatName = 'Invocations' 
group by to_char(StarDate,'rrrr-mm-dd HH24:')||'00', APIName

有多种方法可以做到这一点。

祝好运！

Answer 4

SQL小提琴

Oracle 11g R2架构设置 ：

CREATE TABLE Data AS
          SELECT '201505071498224437562706' AS StatKey, TO_DATE( '2015-05-07 14:12:44', 'YYYY-MM-DD HH24:MI:SS' ) AS StartDate, TO_DATE( '2015-05-07 14:22:44', 'YYYY-MM-DD HH24:MI:SS' ) AS EndDate, 'API5' AS APIName, 'Invocations' AS StatName, 34 AS StatValue FROM DUAL
UNION ALL SELECT '201505071498161437466684' AS StatKey, TO_DATE( '2015-05-07 14:06:14', 'YYYY-MM-DD HH24:MI:SS' ) AS StartDate, TO_DATE( '2015-05-07 14:16:14', 'YYYY-MM-DD HH24:MI:SS' ) AS EndDate, 'API4' AS APIName, 'Invocations' AS StatName, 79 AS StatValue FROM DUAL
UNION ALL SELECT '201505071498060937466556' AS StatKey, TO_DATE( '2015-05-07 13:56:08', 'YYYY-MM-DD HH24:MI:SS' ) AS StartDate, TO_DATE( '2015-05-07 14:06:08', 'YYYY-MM-DD HH24:MI:SS' ) AS EndDate, 'API4' AS APIName, 'Average' AS StatName, 26264.37 AS StatValue FROM DUAL
UNION ALL SELECT '201505071497263437627286' AS StatKey, TO_DATE( '2015-05-07 14:16:33', 'YYYY-MM-DD HH24:MI:SS' ) AS StartDate, TO_DATE( '2015-05-07 14:26:34', 'YYYY-MM-DD HH24:MI:SS' ) AS EndDate, 'API2' AS APIName, 'Invocations' AS StatName, 24 AS StatValue FROM DUAL
UNION ALL SELECT '201505071497262137620812' AS StatKey, TO_DATE( '2015-05-07 14:16:19', 'YYYY-MM-DD HH24:MI:SS' ) AS StartDate, TO_DATE( '2015-05-07 14:26:20', 'YYYY-MM-DD HH24:MI:SS' ) AS EndDate, 'API2' AS APIName, 'Invocations' AS StatName, 24 AS StatValue FROM DUAL
UNION ALL SELECT '201505071497024537466378' AS StatKey, TO_DATE( '2015-05-07 13:52:43', 'YYYY-MM-DD HH24:MI:SS' ) AS StartDate, TO_DATE( '2015-05-07 14:02:44', 'YYYY-MM-DD HH24:MI:SS' ) AS EndDate, 'API1' AS APIName, 'Average' AS StatName, 6830050 AS StatValue FROM DUAL
UNION ALL SELECT '201505071497023337466368' AS StatKey, TO_DATE( '2015-05-07 13:52:31', 'YYYY-MM-DD HH24:MI:SS' ) AS StartDate, TO_DATE( '2015-05-07 14:02:32', 'YYYY-MM-DD HH24:MI:SS' ) AS EndDate, 'API3' AS APIName, 'Average' AS StatName, 31523 AS StatValue FROM DUAL
UNION ALL SELECT '201505071496023337466361' AS StatKey, TO_DATE( '2015-05-07 13:52:31', 'YYYY-MM-DD HH24:MI:SS' ) AS StartDate, TO_DATE( '2015-05-07 14:02:32', 'YYYY-MM-DD HH24:MI:SS' ) AS EndDate, 'API2' AS APIName, 'Invocations' AS StatName, 1 AS StatValue FROM DUAL
UNION ALL SELECT '201505071494263837628892' AS StatKey, TO_DATE( '2015-05-07 14:16:36', 'YYYY-MM-DD HH24:MI:SS' ) AS StartDate, TO_DATE( '2015-05-07 14:26:37', 'YYYY-MM-DD HH24:MI:SS' ) AS EndDate, 'API5' AS APIName, 'Invocations' AS StatName, 68 AS StatValue FROM DUAL
UNION ALL SELECT '201505071493124437466656' AS StatKey, TO_DATE( '2015-05-07 14:02:44', 'YYYY-MM-DD HH24:MI:SS' ) AS StartDate, TO_DATE( '2015-05-07 14:12:44', 'YYYY-MM-DD HH24:MI:SS' ) AS EndDate, 'API1' AS APIName, 'Invocations' AS StatName, 2 AS StatValue FROM DUAL
UNION ALL SELECT '201505071492263037625304' AS StatKey, TO_DATE( '2015-05-07 14:16:29', 'YYYY-MM-DD HH24:MI:SS' ) AS StartDate, TO_DATE( '2015-05-07 14:26:30', 'YYYY-MM-DD HH24:MI:SS' ) AS EndDate, 'API3' AS APIName, 'Average' AS StatName, 179223.29 AS StatValue FROM DUAL;

查询1 ：

SELECT   TRUNC( EndDate, 'HH' ) AS "Date&Hour",
         APIName,
         SUM( StatValue ) AS Invocations
FROM     Data
WHERE    StatName = 'Invocations'
GROUP BY TRUNC( EndDate, 'HH' ),
         APIName

结果 ：

|             Date&Hour | APINAME | INVOCATIONS |
|-----------------------|---------|-------------|
| May, 07 2015 14:00:00 |    API2 |          49 |
| May, 07 2015 14:00:00 |    API5 |         102 |
| May, 07 2015 14:00:00 |    API1 |           2 |
| May, 07 2015 14:00:00 |    API4 |          79 |

Answer 5

日期函数似乎很难以数据库不可知的方式实现。

对于数据库不可知的解决方案，我建议在数据库中创建视图，以隐藏特定于数据库的代码的实现，因此，您可以使用直接选择而不会出现任何语法问题。