如何選擇oracle的計數值sql

Question

感謝我的一位朋友，我已經能夠獲得以下代碼，該代碼給出了基於30分鐘差異的日期/時間計數。如果差值小於30分鐘比數保持不變，否則，如果該值大於計數由1

SELECT 
CASE 
     WHEN DATE2 - LAG(DATE2) over (PARTITION BY NAME, TRUNC(DATE2) ORDER BY DATE2) <= 1/48 
     THEN NULL 
     ELSE 1 
     END AS COUNT1 
FROM TABLE1 

什麼我忘了問他有上升的是，已經被算作值開始計時的時間和結束時間，因爲這可以讓我鍛鍊花費了多長時間，但是我不確定如何根據上面的代碼添加它，所以沒有嘗試任何東西。

我將不勝感激，如果有人可以請建議我如何可以帶來這樣的事情，因爲SQL不是我最強的一點。

下面是一些示例數據：

NAME | DATE2 
Humpty Dumpty | 21-JUL-16 09:27:24 
Humpty Dumpty | 21-JUL-16 09:27:24 
Humpty Dumpty | 21-JUL-16 09:27:24 
Humpty Dumpty | 21-JUL-16 09:27:24 
Humpty Dumpty | 21-JUL-16 09:31:31 
Humpty Dumpty | 21-JUL-16 09:31:31 
Humpty Dumpty | 21-JUL-16 09:31:31 
Humpty Dumpty | 21-JUL-16 09:31:31 
Humpty Dumpty | 21-JUL-16 16:42:03 
Humpty Dumpty | 21-JUL-16 16:42:03 
Humpty Dumpty | 21-JUL-16 16:42:03 
Humpty Dumpty | 21-JUL-16 16:42:03 

當我運行上面的查詢我得到如下：

Count1 
1 
(null) 
(null) 
(null) 
(null) 
(null) 
(null) 
(null) 
1 
(null) 
(null) 
(null) 

這給了我的價值，但我還需要知道的第一個值因爲當1被計數並且下一個值之前的最後一個值被計數時。

從我上面的結果應該是這樣的：

Count1 | Start_time | End_Time 
1 | 21-JUL-16 09:27:24 | 21-JUL-16 09:31:31 
1 | 21-JUL-16 16:42:03 | 21-JUL-16 16:42:03 

有一點需要指出的是，如果有半小時的同一天另一個值，然後開始時間也結束時間..

Answer 1

你想識別不同的組。因爲您使用的是lag()方法，我會繼續這樣做。下一步是一個累計總和，然後聚合：

SELECT NAME, TRUNC(DATE2), MIN(DATE2), MAX(DATE2) 
FROM (SELECT t1.*, 
      SUM(COUNT1) OVER (PARTITION BY NAME, TRUNC(DATE2) ORDER BY DATE2) as grp 
     FROM (SELECT t1.*, 
        (CASE WHEN DATE2 - LAG(DATE2) over (PARTITION BY NAME, TRUNC(DATE2) ORDER BY DATE2) <= 1/48 
         THEN 0 ELSE 1 
        END) AS COUNT1 
      FROM TABLE1 t1 
      ) t1 
    ) t1 
GROUP BY NAME, TRUNC(DATE2), grp; 

Answer 2

DATE2 

是當前行上的時間 - 在計算，這是結束時間

LAG(DATE2) over (PARTITION BY NAME, TRUNC(DATE2) ORDER BY DATE2) 

是前一行的時間（當按日期排序時） - 在計算中，這是開始時間

它確實如此簡單。

我更新了以下內容（希望）以符合您的更新要求。

查詢A使用LAG和LEAD函數來確定每行是否位於一組條目的開始位置（前一行> 30分鐘差異）或一組條目的末尾（下一行> 30分鐘差異）

查詢乙然後將結果限制行，它們或者開始或結束行（一切僅僅是噪聲）

最後每個開始和結束連接在一起成一個單一的一行。

WITH 
test_data (name, date2) AS 
    (SELECT 'Humpty Dumpty',TO_DATE('21/07/2016 09:27:24','DD/MM/YYYY HH24:MI:SS') FROM DUAL UNION ALL 
    SELECT 'Humpty Dumpty',TO_DATE('21/07/2016 09:27:24','DD/MM/YYYY HH24:MI:SS') FROM DUAL UNION ALL 
    SELECT 'Humpty Dumpty',TO_DATE('21/07/2016 09:27:24','DD/MM/YYYY HH24:MI:SS') FROM DUAL UNION ALL 
    SELECT 'Humpty Dumpty',TO_DATE('21/07/2016 09:27:24','DD/MM/YYYY HH24:MI:SS') FROM DUAL UNION ALL 
    SELECT 'Humpty Dumpty',TO_DATE('21/07/2016 09:31:31','DD/MM/YYYY HH24:MI:SS') FROM DUAL UNION ALL 
    SELECT 'Humpty Dumpty',TO_DATE('21/07/2016 09:31:31','DD/MM/YYYY HH24:MI:SS') FROM DUAL UNION ALL 
    SELECT 'Humpty Dumpty',TO_DATE('21/07/2016 09:31:31','DD/MM/YYYY HH24:MI:SS') FROM DUAL UNION ALL 
    SELECT 'Humpty Dumpty',TO_DATE('21/07/2016 09:31:31','DD/MM/YYYY HH24:MI:SS') FROM DUAL UNION ALL 
    SELECT 'Humpty Dumpty',TO_DATE('21/07/2016 09:40:00','DD/MM/YYYY HH24:MI:SS') FROM DUAL UNION ALL 
    SELECT 'Humpty Dumpty',TO_DATE('21/07/2016 09:40:00','DD/MM/YYYY HH24:MI:SS') FROM DUAL UNION ALL 
    SELECT 'Humpty Dumpty',TO_DATE('21/07/2016 16:42:03','DD/MM/YYYY HH24:MI:SS') FROM DUAL UNION ALL 
    SELECT 'Humpty Dumpty',TO_DATE('21/07/2016 16:42:03','DD/MM/YYYY HH24:MI:SS') FROM DUAL UNION ALL 
    SELECT 'Humpty Dumpty',TO_DATE('21/07/2016 16:42:03','DD/MM/YYYY HH24:MI:SS') FROM DUAL UNION ALL 
    SELECT 'Humpty Dumpty',TO_DATE('21/07/2016 16:45:03','DD/MM/YYYY HH24:MI:SS') FROM DUAL UNION ALL 
    SELECT 'Humpty Dumpty',TO_DATE('21/07/2016 16:45:03','DD/MM/YYYY HH24:MI:SS') FROM DUAL UNION ALL 
    SELECT 'Humpty Dumpty',TO_DATE('21/07/2016 18:00:03','DD/MM/YYYY HH24:MI:SS') FROM DUAL UNION ALL 
    SELECT 'Humpty Dumpty',TO_DATE('21/07/2016 18:00:03','DD/MM/YYYY HH24:MI:SS') FROM DUAL UNION ALL 
    SELECT 'Humpty Dumpty',TO_DATE('21/07/2016 18:00:03','DD/MM/YYYY HH24:MI:SS') FROM DUAL UNION ALL 
    SELECT 'ABC',TO_DATE('21/07/2016 18:00:03','DD/MM/YYYY HH24:MI:SS') FROM DUAL UNION ALL 
    SELECT 'ABC',TO_DATE('21/07/2016 18:10:03','DD/MM/YYYY HH24:MI:SS') FROM DUAL UNION ALL 
    SELECT 'ABC',TO_DATE('21/07/2016 18:50:03','DD/MM/YYYY HH24:MI:SS') FROM DUAL UNION ALL 
    SELECT 'ABC',TO_DATE('21/07/2016 18:51:03','DD/MM/YYYY HH24:MI:SS') FROM DUAL 
) 
SELECT 
name 
,TO_CHAR(start_time,'DD/MM/YYYY HH24:MI:SS')  start_time 
,TO_CHAR(end_time,'DD/MM/YYYY HH24:MI:SS')  end_time 
FROM 
--Query B 
(SELECT 
    name 
    ,date2          start_time 
    ,LEAD(date2) OVER (PARTITION BY name,TRUNC(date2) ORDER BY date2) end_time 
    ,start_flag 
    FROM 
    --Query A 
    (SELECT 
    name 
    ,date2 
    ,CASE 
     WHEN date2 - LAG(date2) OVER (PARTITION BY name, TRUNC(date2) ORDER BY date2) <= (1/48) 
     THEN 'N' 
     ELSE 'Y' 
    END          start_flag 
    ,CASE 
     WHEN LEAD(date2) OVER (PARTITION BY name, TRUNC(date2) ORDER BY date2) - date2 <= (1/48) 
     THEN 'N' 
     ELSE 'Y' 
    END          end_flag 
    FROM 
    test_data 
    ORDER BY 
    name 
    ,date2 
    ) 
    WHERE 1=1 
    AND (start_flag = 'Y' OR end_flag = 'Y') 
) 
WHERE start_flag = 'Y' 
;