在R数据框中转换间隔外部联接SQL [英] Convert Interval Outer Join SQL in R data frame

问题描述

之前，我在Python中遇到相同的问题：转换间隔外部联接到Python Pandas Dataframe中的SQL
，我想在R中完成。

I have a same problem in Python before: Convert Interval Outer Join SQL in Python Pandas Dataframe and I would like to do it in R.

我正在转换Oracle SQL外部间隔联接到R。下面是Oracle SQL：

I'm converting an Oracle SQL outer interval join into R. Below is the Oracle SQL:

WITH df_interval AS
          (SELECT '1' id,
                     'AAA' interval,
                     1000 begin,
                     2000 end
              FROM DUAL
            UNION ALL
            SELECT '1' id,
                     'BBB' intrvl,
                     2100 begin,
                     3000 end
              FROM DUAL
            UNION ALL
            SELECT '2' id,
                     'CCC' intrvl,
                     3100 begin,
                     4000 end
              FROM DUAL
            UNION ALL
            SELECT '2' id,
                     'DDD' intrvl,
                     4100 begin,
                     5000 end
              FROM DUAL),
      df_point AS
          (SELECT '1' id, 'X1' point, 1100 mid FROM DUAL
            UNION ALL
            SELECT '1' id, 'X2' point, 2050 mid FROM DUAL
            UNION ALL
            SELECT '1' id, 'X3' point, 3200 mid FROM DUAL
            UNION ALL
            SELECT '2' id, 'X4' point, 4200 mid FROM DUAL
            UNION ALL
            SELECT '2' id, 'X5' point, 5500 mid FROM DUAL)
SELECT pt.id,
         point,
         mid,
         interval
  FROM df_interval it RIGHT OUTER JOIN df_point pt ON pt.id = it.id AND pt.mid BETWEEN it.begin AND it.end

我期望这样的结果：

  ID point   mid interval
0  1    X1  1100      AAA
1  1    X2  2050      NaN
2  1    X3  3200      NaN
3  2    X4  4200      DDD
4  2    X5  5500      NaN

是否有人可以帮助我？

推荐答案

以下是使用 data.table 软件包的选项：

Here is an option using data.table package:

library(data.table)
setDT(df_interval)
setDT(df_point)
df_interval[df_point, on=.(id, begin<=mid, end>=mid),
    .(ID=id, point=i.point, mid=i.mid, interval=x.interval)]

输出：

   ID point  mid interval
1:  1    X1 1100      AAA
2:  1    X2 2050     <NA>
3:  1    X3 3200     <NA>
4:  2    X4 4200      DDD
5:  2    X5 5500     <NA>

数据：

df_interval <- data.frame(id=c(1,1,2,2), 
    interval=c('AAA','BBB','CCC','DDD'),
    begin=c(1000,2100,3100,4100),
    end=c(2000,3000,4000,5000))
df_point <- data.frame(id=c(1,1,1,2,2),
    point=c('X1','X2','X3','X4','X5'),
    mid=c(1100,2050,3200,4200,5500))

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