获得大于零的最小值

Question

我有下表:

column1   column2   column3
   3         2         0
   5         9         2
   1         4         6

当我运行以下代码时:

SELECT
  id_function = @param,
  MIN(t1.column1) AS c1min, 
  MAX(t1.column2) AS c2max,
  MIN(t1.column3) AS c3min
FROM
  table1 (NOLOCK) AS t1
WHERE
  t1.id = @param

我明白了:

c1min   c2max   c3min
  1       9       0

我的问题是c3min必须是大于零的最小值.我需要的结果应该是:

c1min   c2max   c3min
  1       9       2

没有使用subselect有没有办法做到这一点？任何帮助将不胜感激.

谢谢!

Answer 1

我建议使用nullif(),以便您的查询

SELECT id_function = @param,
   MIN(t1.column1) AS c1min, 
   MAX(t1.column2) AS c2max,
   MIN(NULLIF(t1.column3,0) AS c3min
FROM table1 (NOLOCK) AS t1
WHERE t1.id = @param

这样你就不会冒险改变你的结果,例如,如果第3列中的真实最小值为100,则前一个答案会影响你的结果,如果你的第3栏中只有零,那么之前的答案也会产生不正确的结果

Answer 2

你可以使用case所设置的0值在您的较高值min()条件

SELECT id_function = @param,
       MIN(t1.column1) AS c1min, 
       MAX(t1.column2) AS c2max,
       MIN(case when t1.column3 = 0 then 99 else t1.column3 end) AS c3min
FROM table1 (NOLOCK) AS t1
WHERE t1.id = @param