按条件查找MIN&MAX值：SQL查询需求及代码优化咨询

查询规则 #

• 优先选取Number值对应Unique_2为MIN的行
• 若同一Unique_1下存在Unique_2不等于MIN的记录，则选取该Unique_1对应的Number值为MAX的行

当前使用的SQL代码 #

select  T1.Unique_1, 
    T1.Unique_2,
    Case WHEN  T2.MIN_Number is not NULL then  T2.MIN_Number ELSE T3.MAX_Number end as Number from Table_1 as T1 LEFT JOIN ( 
SELECT  Unique_1,
        MIN(Number) as MIN_Number
From Table_1 WHERE Unique_2 = 'MIN' 
GROUP BY Unique_1) AS T2 ON  T1.Unique_1 = T2.Unique_1 LEFT JOIN( 
SELECT  Unique_1, 
        MAX(Number) as MAX_Number 
From Table_1 WHERE Unique_2 = 'MAX' 
GROUP BY Unique_1) AS T3 ON  T1.Unique_1 = T3.Unique_1 

当前代码无法正确实现上述查询逻辑，请求提供符合规则的SQL实现思路与修正方案。

内容的提问来源于stack exchange，提问作者Petras