我有两个表DATA和EVENTS，其中包含以下数据：
EVENTS
EventIndex ObjID LocID EventData EventTime EventType
83707365 3519434 10376 0 2013-05-19 11:32:11 137
83707849 3519434 10374 0 2013-05-19 11:35:18 137
83714233 888799 10376 0 2013-05-19 12:24:45 137
83715200 888799 10184 0 2013-05-19 12:32:18 137
DATA
EventIndex TagName TagValue
83714233 ObjName Peter
83714233 LocName H118
83715200 ObjName Peter
83715200 LocName H116
83707365 ObjName John
83707365 LocName H118
83707849 ObjName John
83707849 LocName H116
从哪里开始SQL SQLLite查询？
我想得到结果：
Name Location Entry Exit Total
Peter H118 12:24:45 12:32:18 00:07:33
John H118 11:32:11 11:35:18 00:03:07
嗨meewoK，可以给出以下案例：
名称位置输入退出总计
彼得H118 12:24:45 12:32:18 00:07:33
John H118 11:32:11 11:35:18 00:03:07
约翰H118 11:44:52 11:45:27 00:00:35
约翰H118 12:31:15 12:32:46 00:01:31
而我正在尝试修改您的查询，但我找不到解决方案。感谢
此代码适用于SQL SERVER：
SELECT E.EventIndex，N.tagvalue AS Name，L.tagvalue AS Location，E.eventtime AS Entry，NEV。[Exit]
从
[事件] E
INNER JOIN [DATA] N ON E.EventIndex = N.eventindex AND N.tagname ='ObjName'
INNER JOIN [DATA] L ON E.EventIndex = L.eventindex AND L.tagname ='LocName'
外部申请（
SELECT TOP（1）NE.eventtime AS [退出]
从
[事件] NE
INNER JOIN [DATA] NL ON NE.EventIndex = NL.eventindex AND NL.tagname ='ObjName'
WHERE
NE.EventIndex＆gt; E.EventIndex
AND NL.tagvalue = N.tagvalue
订购单
NE.EventIndex
) NEV
何处L.tagvalue ='H118'
有人可以帮我把它传递给SQLite吗？ 感谢
答案 0 :(得分：0)
这是一个用于处理表的快速SQL转储。
CREATE TABLE EVENTS (EventIndex int, objID int, eventtime datetime);
INSERT INTO "EVENTS" VALUES(83707365,3519434,'2013-05-19 11:32:11');
INSERT INTO "EVENTS" VALUES(83707849,3519434,'2013-05-19 11:35:18');
INSERT INTO "EVENTS" VALUES(83714233,888799,'2013-05-19 12:24:25');
INSERT INTO "EVENTS" VALUES(83714233,888799,'2013-05-19 12:32:18');
CREATE TABLE DATA (eventindex int, tagname char, tagvalue char);
INSERT INTO "DATA" VALUES(83714233,'ObjName','Peter');
INSERT INTO "DATA" VALUES(83714233,'LocName','H118');
INSERT INTO "DATA" VALUES(83715200,'ObjName','Peter');
INSERT INTO "DATA" VALUES(83715200,'LocName','H118');
INSERT INTO "DATA" VALUES(83707365,'ObjName','John');
INSERT INTO "DATA" VALUES(83707849,'ObjName','John');
INSERT INTO "DATA" VALUES(83707365,'LocName','H118');
INSERT INTO "DATA" VALUES(83707849,'LocName','H118');
第1步，获取每个eventtype的最大和最小ObjID：
SELECT ObjID, Min(EventIndex) as EventIndex, Min(EventTime) as Entry, Max(EventTime) as Exit
FROM EVENTS GROUP BY ObjID;
ObjID EventIndex Entry Exit
3519434 83707365 12:24:45 12:32:18
888799 83714233 11:32:11 11:25:18
现在，这揭示了数据结构的一些问题。对于每个ObjID，您有两个EventIndex，那么您应该选择哪一个？{1}}在这里，我只选择了两者中的第一个（最小的）。
第2步，因为sqlite3不喜欢对聚合执行操作，我们将其变为视图：
CREATE VIEW single_events AS
SELECT ObjID, Min(EventIndex) as EventIndex, Min(EventTime) as Entry, Max(EventTime) as Exit FROM EVENTS GROUP BY ObjID;
步骤3，通过操作视图获取总时间：
SELECT *, time(strftime('%s', exit) - strftime('%s', entry), 'unixepoch') as total
FROM single_events;
ObjID EventIndex Entry Exit total
---------- ---------- ------------------- ------------------- ----------
888799 83714233 2013-05-19 12:24:25 2013-05-19 12:32:18 00:07:53
3519434 83707365 2013-05-19 11:32:11 2013-05-19 11:35:18 00:03:07
步骤4，将其与DATA合并。
SELECT d1.TagValue as Name, d2.TagValue as Location, Entry, Exit, time(strftime('%s', exit) - strftime('%s', entry), 'unixepoch') as total
FROM single_events
LEFT JOIN DATA as d1 USING (EventIndex)
LEFT JOIN DATA as d2 USING (EventIndex)
WHERE d1.tagname = 'ObjName' AND d2.tagname = 'LocName';
当然，如果它是一个非常大的数据集，您可能会在运行第4步之前将d1和d2放入临时表中。
答案 1 :(得分：0)
这样的事情可以让你很好地开始：
SQL小提琴：http://www.sqlfiddle.com/#!2/6e6a7/33
SELECT d.TagValue AS Name,
d2.TagValue AS LOCATION,
e.eventTime AS Entry,
( SELECT eventtime
FROM EVENTS e2
WHERE e2.objID = e.objID
AND e2.eventTime > e.eventTime LIMIT 1) AS ExitTime,
(e.eventTime -
( SELECT eventtime
FROM EVENTS e2
WHERE e2.objID = e.objID
AND e2.eventTime > e.eventTime LIMIT 1)) AS TotalTime
FROM events e,
DATA d,
DATA d2
WHERE e.eventIndex = d.eventIndex
AND e.eventIndex = d2.eventIndex
AND d.TagName = "ObjName"
AND d2.TagName = "LocName"
AND mod(
( SELECT count(*)
FROM EVENTS e2
WHERE e2.objID = e.objID
AND e2.eventTime < e.eventTime),2) = 0
ORDER BY EventTime;
结果：
NAME LOCATION ENTRY EXITTIME TOTALTIME
John H118 May, 19 2013 11:32:11+0000 May, 19 2013 11:35:18+0000 -307
Peter H118 May, 19 2013 12:24:45+0000 May, 19 2013 12:32:18+0000 -773
我添加了额外的事件，以证明退出一个被视为另一个事件的事件。
如果我们说进入和退出不能在不同日期发生，则可以优化上述查询，例如USER进入11.59PM并离开1.00AM ...
SELECT d.TagValue AS Name,
d2.TagValue AS LOCATION,
e.eventTime AS Entry,
( SELECT eventtime
FROM EVENTS e2
WHERE e2.objID = e.objID
AND e2.eventTime > e.eventTime LIMIT 1) AS ExitTime,
(e.eventTime -
( SELECT eventtime
FROM EVENTS e2
WHERE e2.objID = e.objID
AND e2.eventTime > e.eventTime AND
DATE(e2.eventTime) = DATE(e.eventTime) LIMIT 1)) AS TotalTime
FROM events e,
DATA d,
DATA d2
WHERE e.eventIndex = d.eventIndex
AND e.eventIndex = d2.eventIndex
AND d.TagName = "ObjName"
AND d2.TagName = "LocName"
AND mod(
( SELECT count(*)
FROM EVENTS e2
WHERE e2.objID = e.objID
AND e2.eventTime < e.eventTime AND
DATE(e2.eventTime) = DATE(e.eventTime)),2) = 0
ORDER BY EventTime;
SQL小提琴：http://www.sqlfiddle.com/#!2/6e6a7/35
这也假设每个entry必须有一个exit，这就是我使用模运算符的原因。
Even的所有Object个活动都是一个条目，所有Odd个活动都是exit。
对于更多条件，显然必须修改查询。
更新：使用SQL Lite（无mod但％）
SQLFiddle：http://www.sqlfiddle.com/#!7/6e6a7/4
SELECT d.TagValue AS Name,
d2.TagValue AS LOCATION,
e.eventTime AS Entry,
( SELECT eventtime
FROM EVENTS e2
WHERE e2.objID = e.objID
AND e2.eventTime > e.eventTime LIMIT 1) AS ExitTime,
(e.eventTime -
( SELECT eventtime
FROM EVENTS e2
WHERE e2.objID = e.objID
AND e2.eventTime > e.eventTime LIMIT 1)) AS TotalTime
FROM events e,
DATA d,
DATA d2
WHERE e.eventIndex = d.eventIndex
AND e.eventIndex = d2.eventIndex
AND d.TagName = "ObjName"
AND d2.TagName = "LocName"
AND (
( SELECT count(*)
FROM EVENTS e2
WHERE e2.objID = e.objID
AND e2.eventTime < e.eventTime)%2) = 0
ORDER BY EventTime;