计算客户的频率

Question

我在sql server上有这个表

cstomer |No_Nota
CUS000     | 98342
CUS000     | 98343
CUS000     | 98343
CUS001     | 98355
CUS001     | 98355

我想计算每个客户的频率。对于相似数量的no_nota，该值为1.

我想要这样的结果：

cstomer |Frequent
CUS000     | 2
CUS001     | 1

Answer 1

您想要列no_nota的明确计数，这就是您应该选择的内容......

select customer, count(distinct no_nota) as frequent
  from my_table
 group by customer

Answer 2

您想要计算选择查询的结果：

    SELECT COUNT(expression)
    FROM tables
    WHERE predicates;

示例：

    SELECT COUNT(No_Nota) FROM your_table WHERE No_Nota > 0;

Answer 3

听起来你只想要一个group by语句来计算所有个人客户的数量。类似的东西：

SELECT cstomer, SUM(1) as Frequent FROM table GROUP BY cstomer, No_Nota