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，我不断收到错误：

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：“SELECT”附近：语法错误

从语法上看，查询有什么问题吗？

Answer 1

您在“人口”一词之后缺少FROM。

Answer 2

您的查询是错误的。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

不正确的查询 ... 第一行中缺少 From 子句。