我怎么做'分组'部分匹配

Question

我在SQL服务器中有一个表,项目代码和子项目代码在相同的字段中.

结构是这样的

+----+------+-------------+-------+--------+--------+
| id | date | projectcode | debit | credit | budget |
+----+------+-------------+-------+--------+--------+
| 1  | bla  | A100        | bla
| 2  | bla  | A100.01     |
| 3  | bla  | A112        |
| 4  | bla  | A112.02

我该怎么做这样的选择

SELECT projectcode
  , sum(debit) as debit
  , sum(credit) as credit
  , sum(budget) as budget
FROM table1
GROUP BY -insert-answer-here-

我希望输出group byA100和A100.01和A100.x以及A112 + A112.x

我该怎么做呢？

我无法控制桌子的结构.

Answer 1

GROUP BY LEFT(projectcode ,CHARINDEX('.',projectcode  + '.')-1)