这个SQL语句在语法上有什么问题吗？

Question

当我尝试在mysqlite3中运行此查询时，我一直收到错误：

SELECT Region_DESC, AgeGroup, Population
(select REGION, sum(POPULATION) as Population, '0-15' AS AgeGroup
from STATS
Where Age between 0 and 15
group by REGION
union
Select REGION, SUM(POPULATION) as Population, '16-30' As AgeGroup
from STATUS
Where Age between 16 and 30
group by REGION) s
join REGION on REGION_CD = REGION

我收到以下错误： 错误：靠近“SELECT”：语法错误

查询是否有任何问题，语法方面？

Answer 1

在“人口”一词之后，你遗漏了FROM。

Answer 2

您的查询错误。你基本上有：

SELECT something
(select somethingelse FROM somethingelsetable) s
join REGION on REGION_CD = REGION

我猜你在括号前缺少FROM ......

Answer 3

错误的查询...在第一行中缺少From Clause。