mysql - SQL 将所有内容打印在一行中

Question

我想分两列打印数据，例如:计数类别

但是我的代码将所有内容打印在一行中，例如:计数类别 计数类别

有什么建议吗？

Select sum(Case when population >= 1000000 and population < 5000000 then 1 else 0 end) as Count, '1 000 000 - 4 999 999' as Category,
   sum(Case when population >= 500000 and population < 100000 then 1 else 1 end) as Count, '100 000 - 499 999' as Category,
   sum(Case when population >= 500000 and population < 100000 then 1 else 1 end) as Count, '500 000 - 999 999' as Category,
   sum(Case when population >= 500000 and population < 100000 then 1 else 1 end) as Count, 'Under 100 000' as Category,
   sum(Case when population >= 500000 and population < 100000 then 1 else 1 end) as Count, 'Over 5 million' as Category
from cities

Answer 1

Select sum(Case when population >= 1000000 and population < 5000000 then 1 else 0 end) as Count, '1 000 000 - 4 999 999' as Category FROM cities
UNION 
SELECT sum(Case when population >= 500000 and population < 100000 then 1 else 1 end) as Count, '100 000 - 499 999' as Category FROM cities

等等...

使用 UNION 关键字将所有单个结果连接到一个结果表中

如果你只想计算城市，那么你的 else in case 部分应该到处都是 0 而不是 1...无论如何，更好的解决方案是

SELECT COUNT(cities.primKey) as Count, '1 000 000 - 4 999 999' as Category FROM cities WHERE population >= 1000000 and population < 5000000
UNION
SELECT COUNT(cities.primKey) as Count, '1 000 000 - 4 999 999' as Category FROM cities WHERE population >= 500000 and population < 100000
UNION ...