Question

此SQLite查询中出现此错误：

select f.rid, c.title, sum(some_expression) as ratio
from doesntmatter
where c.active = 1 or (ratio = 1.0 and c.active = 0
      and c.deactivated in (1, 2, 3, 4, 5)
group by f.rid

This问题通过having子句解决了这个问题：

select f.rid, c.title, sum(some_expression) as ratio
from doesntmatter
where c.active = 1 or (c.active = 0
      and c.deactivated in (1, 2, 3, 4, 5)
group by f.rid
having ratio = 1.0

但在我的情况下，这会改变表达式的语义。你知道如何实现原始where子句中的表达式吗？

Answer 1

基本上，您不能在where子句中引用别名列。请查看此question，了解如何解决此问题。

另外，您应该使用select语句中出现的所有非汇总列添加到组中，在本例中为c.id和c.title。

很难为你重写那个查询，因为逻辑有点难以理解（因为错误的分组）。

修改

经过一番思考，您可能只需要更正group by。

select c.id, c.title, sum(some_expression) as ratio from doesntmatter where c.active = 1 or (c.active = 0 and c.deactivated in (1, 2, 3, 4, 5)) group by c.id, c.title having ratio = 1.0

或者也许：

select f.rid, sum(some_expression) as ratio from doesntmatter where c.active = 1 or (c.active = 0 and c.deactivated in (1, 2, 3, 4, 5)) group by f.rid having ratio = 1.0

我无法帮助你完成上一部分，因为我不知道你的表的字段和数据，也不知道如何解释它们。但选择不在组中的字段是一个坏主意。无论如何，请记住，您可以随时加入原始表格并获取您要查找的信息，而不仅仅是select中显示的字段。

在SQLite中滥用聚合

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