Sql : 不错。我只会使用（t1.begin，t1.end+INTERVAL'1'天）。我想如果没有这个改变，一些边缘案例可能会显示错误。@Adam:我不知道。因此，也许一个+间隔'2'天可能适合捕捉这种情况2000-01-01-2001-12-31和2002-

:

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不错。我只会使用

（t1.begin，t1.end+INTERVAL'1'天）

。我想如果没有这个改变，一些边缘案例可能会显示错误。@Adam:我不知道。因此，也许一个

+间隔'2'天

可能适合捕捉这种情况

2000-01-01-2001-12-31

和

2002-01-01-2002-06-31

。这不是每个ID只返回一个范围吗？还有一件事，我起初没有注意到。这两个条件绝对不能同时应用：

t1.id=r.id和t1.id>r.id

。感谢您的评论和观察。这个额外的条件只适用于我测试这个查询的表。我现在已经将其更改为适合Marcel的表格。嗯，我认为这个解决方案存在一个问题：使用min（开始）时，您得到第一个“开始”条目，使用max（结束）时，您得到最后一个“结束”条目。但是，您可能会丢失第一个“开始”和最后一个“结束”之间所有“开始”和“结束”的信息。您可以计算最小值和最大值之间的差异，然后对每一行计算其各自的最小值和最大值，如果该数字低于第一个，则表示计划中有空闲天数。这就是我最初的想法：）它在我认为的每种情况下都能工作，具体取决于您如何实现：）“有没有一种方法可以不用窗口函数和查询？”--可能没有，因为您需要在某一点或另一点递归合并行。我明白了-谢谢。因此，我的尝试是没有出路的？我的意思是它给了我所有需要的行，我唯一的困难是排除不需要的行。然而，我已经要求我的管理员更新postgresql服务器。希望他会这么好。如果没有递归查询，您可以在curr上找到使用大型（且非常缓慢）连接的边界。开始查看此相关线程：另请参见：

ID    BEGIN    END

SELECT "ID", MIN("BEGIN"), MAX("END")
FROM ...
GROUP BY "ID"

SELECT "ID", LEAST(tab1."BEGIN", tab2."BEGIN"), GREATEST(tab1."END", tab2."END")
  FROM <mytable> AS tab1
  JOIN <mytable> AS tab2
    ON tab1."ID" = tab2."ID"
    AND  (tab1."BEGIN", tab1."END" + INTERVAL '2 day') OVERLAPS (tab2."BEGIN", tab2."END")
  ORDER BY "ID"

ID        BEGIN         END
1;"2000-01-01";"2000-03-31"  
1;"2000-04-01";"2000-05-31"  
1;"2000-04-15";"2000-07-31"  
1;"2000-09-01";"2000-10-31"  
2;"2000-02-01";"2000-03-15"  
2;"2000-01-15";"2000-03-31"  
2;"2000-04-01";"2000-04-15"  
3;"2000-06-01";"2000-06-15"  
3;"2000-07-01";"2000-07-15"  

ID        BEGIN         END
1;"2000-01-01";"2000-07-31"
1;"2000-09-01";"2000-10-31"
2;"2000-01-15";"2000-04-15"
3;"2000-06-01";"2000-06-15"
3;"2000-07-01";"2000-07-15"

WITH
  t1 AS (
    SELECT id, begin AS time
      FROM "nace-8510-test".checkfkt
    UNION ALL
    SELECT id, end
      FROM "nace-8510-test".checkfkt
  ),

  t2 AS (
    SELECT Row_Number() OVER(PARTITION BY id ORDER BY time) AS num, id, time
      FROM t1 AS t1_1
  ),

  t3 AS (
    SELECT t2_1.num - Row_Number() OVER(PARTITION BY t2_1.id ORDER BY t2_1.time, t2_2.time) num1,
        t2_1.id, t2_1.time AS begin, t2_2.time AS end
      FROM t2 AS t2_1
        INNER JOIN t2 AS t2_2
          ON t2_1.id = t2_2.id
            AND t2_1.num = t2_2.num - 1
      WHERE
        EXISTS (
          SELECT *
            FROM "nace-8510-test".checkfkt AS s
            WHERE s.id = t2_1.id
              AND (s.begin < t2_2.time AND s.end > t2_1.time)
        )
        OR t2_1.time = t2_2.time
        OR t2_1.time + INTERVAL '1 day' = t2_2.time
  )

SELECT id, MIN(begin) AS von, MAX(end) AS bis
  FROM t3
  GROUP BY id, num1
  ORDER BY id

select id,
       lag(start) over w as prev_start,
       lag(end) over w as prev_end,
       start,
       end,
       lead(start) over w as next_start,
       lead(end) over w as next_end
from yourtable
window w as (
       partition by id
       order by start, end
       )

WITH RECURSIVE t1_rec ( id, "begin", "end", n ) AS (
    SELECT id, "begin", "end", n
      FROM (
        SELECT
            id, "begin", "end",
            CASE 
                WHEN LEAD("begin") OVER (
                PARTITION BY    id
                ORDER BY        "begin") <= ("end" + interval '2' day) 
                THEN 1 ELSE 0 END AS cl,
            ROW_NUMBER() OVER (
                PARTITION BY    id
                ORDER BY        "begin") AS n
        FROM mytable 
    ) s
    WHERE s.cl = 1
  UNION ALL
    SELECT p1.id, p1."begin", p1."end", a.n
      FROM t1_rec a 
           JOIN mytable p1 ON p1.id = a.id
       AND p1."begin" > a."begin"
       AND (a."begin",  a."end" + interval '2' day) OVERLAPS 
           (p1."begin", p1."end")
)
SELECT t1.id, min(t1."begin"), max(t1."end")
  FROM t1_rec t1
       LEFT JOIN t1_rec t2 ON t1.id = t2.id 
       AND t2."end" = t1."end"
       AND t2.n < t1.n
 WHERE t2.n IS NULL
 GROUP BY t1.id, t1.n
 ORDER BY t1.id, t1.n;

WITH RECURSIVE rec_stmt ( id, begin, end ) AS (
    /* seed statement: 
           start with only first start and end dates for each id 
    */
      SELECT id, MIN(begin), MIN(end)
        FROM mytable seed_stmt
    GROUP BY id

    UNION ALL

    /* iterative (not really recursive) statement: 
           append qualifying rows to resultset 
    */
      SELECT t1.id, t1.begin, t1.end
        FROM rec_stmt r
             JOIN mytable t1 ON t1.id = r.id
         AND t1.begin > r.end
         AND (r.begin, r.end + INTERVAL '1' DAY) OVERLAPS 
             (t1.begin - INTERVAL '1' DAY, t1.end)
)
  SELECT MIN(begin), MAX(end) 
    FROM rec_stmt
GROUP BY id;

COPY (
  SELECT "ID", "BEGIN", "END"
  <sorry, for a reason I don't know StackOverflow won't let me finish my code here...>

data - read.csv2("</path/to.csv>")
data$BEGIN - as.Date(data$BEGIN)
data$END - as.Date(data$END)

smoothingEpisodes - function (theData) {

    theLength - nrow(theData)
    if (theLength  2L) return(theData)

    ID - as.integer(theData[["ID"]])
    BEGIN - as.numeric(theData[["BEGIN"]])
    END - as.numeric(theData[["END"]])

    curId - ID[[1L]]
    curBEGIN - BEGIN[[1L]]
    curEND - END[[1L]]



    out.1 - integer(length = theLength)
    out.2 - out.3 - numeric(length = theLength)

    j - 1L

    for(i in 2:nrow(theData)) {
        nextId - ID[[i]]
        nextBEGIN - BEGIN[[i]]
        nextEND - END[[i]]

        if (curId != nextId | (curEND + 1)  nextBEGIN) {
            out.1[[j]] - curId
            out.2[[j]] - curBEGIN
            out.3[[j]] - curEND

            j - j + 1L

            curId - nextId
            curBEGIN - nextBEGIN
            curEND - nextEND
        } else {
            curEND - max(curEND, nextEND, na.rm = TRUE)
        }
    }

    out.1[[j]] - curId
    out.2[[j]] - curBEGIN
    out.3[[j]] - curEND

    theOutput - data.frame(ID = out.1[1:j], BEGIN = as.Date(out.2[1:j], origin = "1970-01-01"), END = as.Date(out.3[1:j], origin = "1970-01-01"))

    theOutput
}

data1 - smoothingEpisodes(data)

data2 - transform(data1, TAGE = (as.numeric(data1$END - data1$BEGIN) + 1))

write.csv2(data2, file = "</path/to/output.csv>")