Question

我需要使用不同的条件过滤数据。一个是如果一个列（d列）中的值是唯一的，如果另一列（c）中的值大于1，则我需要质疑。

让我们假设：栏a，b，c，d

因此，我不希望任何条目，其中c大于1而d具有非唯一值。

Select TOP 100 * From table
Where (a = 'Max' AND b = '2019') -- just an additional filter, which always applies
    AND (c = 1 -- if c is one, that is fine
            OR (c > 1 AND -- here I want to check if c is bigger than 1 AND if d is unique; but thats the part I need help with
        );

非常感谢您！

Answer 1

创建一个CTE，您可以在其中计算列d的不同值，并在WHERE子句中使用它：

with cte as (
  select count(distinct d) counter from tablename
)
...........................................
Where ....(c > 1 AND (select counter from cte) = 1)

不同条件（类似于IF）+唯一值

1 个答案: