SQL 查询以查找列的行值之间的最小差异

Question

我正在尝试找出每个 ID 的年份之间的最小差异。例如，

我有这个数据：

ID     year
1      2001
1      2001
2      2003
2      2004
2      2010
3      2000

我想要这个输出：

ID    year
1      0
2      1
3      0

Answer 1

您可以使用 lag():

select id, coalesce(min(year - prev_year), 0)
from (select t.*, lag(year) over (partition by id order by year) as prev_year
      from t
     ) t
group by id;

Here 是一个 db<>fiddle.

Answer 2

您可以使用 LEFT JOIN

SELECT Id,
       ISNULL(MIN(Def), 0) [Year]
FROM
(
  SELECT T.Id,
         TT.Year - T.Year Def
  FROM Data T
  LEFT JOIN Data TT ON T.Id = TT.Id AND T.Year < TT.Year
) T
GROUP BY Id;

Online Demo