SQL除以兩個計數（）

Question

我有以下查詢，它試圖找出某個產品與產品總數相比的百分比。 IE：[產品數量] / [總產品數量] =百分比

;WITH totalCount AS(
    SELECT 
        CAST(COUNT(id) as Integer)as totalCount
    FROM TABLE_NAME
)
SELECT 
    ((CAST(COUNT(DISTINCT id) as Integer)/(SELECT * FROM totalCount))*100) as 'Percent'
FROM TABLE_NAME

但是，除非只有一條記錄，否則百分比列始終返回“0”。 另外，有沒有辦法將totalCount和Select查詢添加到一個？

基本上，你如何划分兩個Count（）字段？

Answer 1

將你的總計數作為除整數之外的數字（DECIMAL？） - 數學四舍五入。

Answer 2

作為具有小數精度的東西，而不是整數。 漂浮或真實。

select cast(distinctCount as real)/cast(totalCount as real) * 100.00
   , distinctCount
   , totalCount
from (
 select count(distinct id) as distinctCount
  , count(id) as totalCount
  from Table) as aggregatedTable

Answer 3

不應該是：

;WITH totalCount AS(
    SELECT 
        CAST(COUNT(id) as Integer)as totalCount
    FROM TABLE_NAME
)
SELECT 
    ((CAST(COUNT(DISTINCT id) as Integer)*100/(SELECT count(*) FROM totalCount))) as 'Percent'
FROM TABLE_NAME

請注意SELECT COUNT（*）。 此外，你應該在划分之前相乘，否則你將總是得到零