提高性能的SQL

Question

这里是我的问题，我有一个表格（在一个Excel表格中，并使用Microsoft.ACE.OLEDB.12.0连接）和各种列，用于跟踪RF读卡器中的进/出卡刷卡下面的格式...

Date, Time Occurred, Employee Number, Employee Name, Location 
2013-12-20, 11:10:23 AM, 123456, Tester, Door001 IN 
2013-12-20, 11:21:44 AM, 123456, Tester, Door002 OUT 
2013-12-20, 12:00:12 AM, 123456, Tester, Door001 IN 
2013-12-20, 01:00:23 PM, 123456, Tester, Door002 IN 
2013-12-20, 03:40:43 PM, 123456, Tester, Door001 OUT 
2013-12-20, 05:00:58 PM, 123456, Tester, Door004 IN 
2013-12-20, 05:50:02 PM, 123456, Tester, Door001 OUT 
2013-12-20, 05:10:00 PM, 123456, Tester, Door002 OUT 
2013-12-20, 11:00:01 PM, 123456, Tester, Door001 IN 
2013-12-20, 09:10:23 AM, 789012, Developer, Door001 IN 
2013-12-20, 10:00:44 AM, 789012, Developer, Door002 OUT 
2013-12-20, 10:01:12 AM, 789012, Developer, Door003 IN 
2013-12-20, 11:00:23 AM, 789012, Developer, Door004 OUT 
2013-12-20, 02:40:43 PM, 789012, Developer, Door005 IN 
2013-12-20, 01:00:58 PM, 789012, Developer, Door006 OUT 
2013-12-20, 06:50:02 PM, 789012, Developer, Door007 IN 
2013-12-20, 08:00:00 PM, 789012, Developer, Door008 IN 
2013-12-20, 09:00:01 PM, 789012, Developer, Door009 OUT 

我要在以下格式输出：

Date,Employee Id, Employee Name, First In Time, First In Door Name, Last out time, Last Out Door Name 
2013-12-20, 123456, Tester, 12:00:12 AM, Door001 IN, 11:00:01 PM, Door001 OUT 
2013-12-20, 789012, Developer, 9:10:23 AM, Door001 IN, 9:00:01 PM, Door009 OUT 

注意第一时间和上次出时间的原始数据，同样首先来自同一列门名和最后门名

我有这个工作，但不表示我认为... 目前，我正在写一个SQL，从源表中获取不同的员工ID。

SELECT DISTINCT [Employee Number] 
FROM [Sheet1$] 

然后我火了两个单独的查询，以获得第一时间和第一门中的名店在Excel和火上期开出另一个查询并持续了门。

SELECT * 
FROM [sheet1$] 
WHERE ([employee number] = '" & Trim(rst.Fields(0).Value) & "') 
     AND (location LIKE '% IN%') 
     AND ( 
[sheet1$].[time occurred] >= '" & Format(startTime, "hh:mm:ss") & "' 
AND [sheet1$].[time occurred] <= '" & Format(endTime, "hh:mm:ss") & "') 
ORDER BY [time occurred] ASC 


SELECT * 
FROM [sheet1$] 
WHERE ([employee number] = '" & Trim(rst.Fields(0).Value) & "') 
     AND (location LIKE '% OUT%') 
     AND ( 
[sheet1$].[time occurred] >= '" & Format(startTime, "hh:mm:ss") & "' 
AND [sheet1$].[time occurred] <= '" & Format(endTime, "hh:mm:ss") & "') 
ORDER BY [time occurred] DESC 

对于给定的时间过滤器，为了得到“第一时间/门”我使用ASC排序和“最后一出/门”，我使用ASC/DESC排序，拿起从第一行结果。问题出现在一个典型的日子里，我可以看到大楼里有大约10000名独特的员工，因此针对每个员工号码发出两个查询（因此20000个查询）需要花费大量时间。此外，为了增加苦恼，我写这是一个VB宏，所以添加循环，如果块的条件等处理，它使得它有点痛苦地慢得到的数据。

只是想，如果我可以避免这些20000查询，并以某种方式只有一个查询所有这些提取，我认为它会更快。任何想法如何我可以通过在一个SQL中作为输出而不是20000个查询来减少逻辑？ 仅供参考，我尝试使用JOIN的但不知何故，我没有得到它:(

Answer 1

查询与动态列：

SELECT E.EMP_ID, 
(SELECT MIN(SWIPE_TIME) FROM SWIPES WHERE EMP_ID = E.EMP_ID AND DOOR_NAME LIKE '%IN%') AS TIME_IN, 
(SELECT DOOR_NAME FROM SWIPES WHERE EMP_ID = E.EMP_ID AND SWIPE_TIME = TIME_IN) AS DOOR_IN, 
(SELECT MAX(SWIPE_TIME) FROM SWIPES WHERE EMP_ID = E.EMP_ID AND DOOR_NAME LIKE '%OUT%') AS TIME_OUT, 
(SELECT DOOR_NAME FROM SWIPES WHERE EMP_ID = E.EMP_ID AND SWIPE_TIME = TIME_OUT) AS DOOR_IN, 
FROM SWIPES E 
GROUP BY E.EMP_ID; 

查询，而不动态列：

SELECT E.EMP_ID, 
(SELECT MIN(SWIPE_TIME) FROM SWIPES WHERE EMP_ID = E.EMP_ID AND DOOR_NAME LIKE '%IN%') AS TIME_IN, 
(SELECT DOOR_NAME FROM SWIPES WHERE EMP_ID = E.EMP_ID AND SWIPE_TIME = 
    (SELECT MIN(SWIPE_TIME) FROM SWIPES WHERE EMP_ID = E.EMP_ID AND DOOR_NAME LIKE '%IN%') 
) AS DOOR_IN, 
(SELECT MAX(SWIPE_TIME) FROM SWIPES WHERE EMP_ID = E.EMP_ID AND DOOR_NAME LIKE '%OUT%') AS TIME_OUT, 

(SELECT DOOR_NAME FROM SWIPES WHERE EMP_ID = E.EMP_ID AND SWIPE_TIME = 
    (SELECT MAX(SWIPE_TIME) FROM SWIPES WHERE EMP_ID = E.EMP_ID AND DOOR_NAME LIKE '%OUT%') 

) AS DOOR_OUT 
FROM SWIPES E 
GROUP BY E.EMP_ID; 

我已经更新了查询作为根据我们的讨论