PostgreSQL-查找和更新多个记录

Question

我有一张桌子：

ID | rows | dimensions
---+------+----------- 
1  |  1   |   15 x 20
2  |  3   |   2  x 10
3  |  5   |   23 x 33
3  |  7   |   15 x 23 
4  |  2   |   12 x 32    

我想要这样的东西：

ID | rows | dimensions
---+------+----------- 
1  |  1   |   15 x 20
2  |  3   |   2  x 10
3a |  5   |   23 x 33
3b |  7   |   15 x 23 
4  |  2   |   12 x 32  

如何找到多个ID值使其唯一？

之后如何更新父表？

谢谢你的帮助！

Answer 1

with stats as (
    SELECT "ID", 
           "rows",
           row_number() over (partition by "ID" order by rows) as rn,
           count(*) over (partition by "ID") as cnt
    FROM Table1
)
UPDATE Table1
   SET "ID" = CASE WHEN s.cnt > 1 THEN s."ID" || '-' || s.rn 
                   ELSE s."ID"
              END
  FROM stats s
 WHERE S."ID" = Table1."ID"
   AND S."rows" = Table1."rows"

我假设你不能有两排相同的ID和同一rows等方面，需要包括"dimensions"的WHERE了。

在这种情况下，输出为