MySql,如何在positve或negative的select查询中进行分组？

Question

我想按所有负面的价值和所有积极的价值观分组,任何想法如何做到这一点？

Answer 1

GROUP BY SIGN(字段)应该有效.

Answer 2

SELECT SUM(CASE WHEN SomeColumn < 0 THEN 1 ELSE 0 END) AS negative_values,
       SUM(CASE WHEN SomeColumn >=0 THEN 1 ELSE 0 END) AS non_negative_values
    FROM YourTable