PostgreSQL通过重叠创建中间阶段

Question

是否可以使用postgresql在上一行和下一行创建中间行？

我有结果

rownumber from to with 
1 1,303 2,88 A 
2 2,88 5,65 A 
3 5,65 8,659 A 
4 8,659 10,342 A 
5 10,33 24,188 B 
6 10,342 26,253 C 
7 26,253 26,38 A 
8 26,38 30,442 A 
9 30,442 35,672 A 

，我需要这个

rownumber from to with 
1 1,303 2,88 A 
2 2,88 5,65 A 
3 5,65 8,659 A 
4 8,659 10,33 A 
    10,33 10,342 A 
5 10,342 24,188 B 

6 24,188 26,253 C 
7 26,253 26,38 A 
8 26,38 30,442 A 
9 30,442 35,672 A 

Answer 1

如果我理解正确的话，simpliest方法是：

WITH x AS (
    SELECT DISTINCT sfrom FROM stages 
    UNION SELECT sto FROM stages 
), y AS (
    SELECT sfrom, row_number() OVER (ORDER BY sfrom) AS i FROM x 
) 
SELECT y2.i, 
     y2.sfrom, 
     y.sfrom as sto, 
     coalesce(x2.swith, x.swith) as xwith 
FROM y JOIN y AS y2 ON (y.i = y2.i + 1) 
LEFT JOIN stages AS x ON (x.sfrom = y2.sfrom) 
LEFT JOIN stages AS x2 ON (x2.sto = y.sfrom) 
ORDER BY 1 
;