Question

我想将数组设置为变量，以便在“IN”子句中的查询中使用它。下面的代码给我一个错误，所以我不确定它是否可能在mysql中。

set @ids = (1,2,3,6);

select 
    sum(promotion_id IN @ids AND confirmed_at IS NOT NULL)
from blabla

我得到两个不同的结果。也就是说，find_in_set和IN（@ids）给我相同的结果，但它与我从IN（1,2,3）获得的结果不同：

set @voda_prom ='1483, 2396, 2395, 1887';

    SUM(FIND_IN_SET(promotion_id,@voda_prom) and confirmed_at IS NOT NULL)*1.0/ SUM(FIND_IN_SET(promotion_id,@voda_prom)) as p,
    SUM(promotion_id IN(1483,2396,2395,1887) and confirmed_at IS NOT NULL)*1.0/ SUM(promotion_id IN(1483,2396,2395,1887)) as p_check,
    SUM(promotion_id IN(@voda_prom) and confirmed_at IS NOT NULL)*1.0/ SUM(promotion_id IN(@voda_prom)) as p_1,

Answer 1

使用find_in_set代替in

set @ids = '1,2,3,6';
select 
    SUM(CASE WHEN FIND_IN_SET(promotion_id,@ids) AND confirmed_at IS NOT NULL THEN 1 ELSE 0 END)
from blabla

此函数与php

中的in_array相同

Answer 2

您可以这样使用：

SET @ids = '1, 2, 3, 6';
select 
    sum(`promotion_id` IN ( @ids)  AND `confirmed_at` IS NOT NULL)
from `blabla`

Answer 3

app.component.ts

mysql：将数组设置为变量以便在“IN”子句中使用

3 个答案: