mysql - SELECT 中的 COUNT() 未产生所需的输出

Question

我有 2 个表:

美国各州城市:

还有usstatescentroids:

SELECT state,COUNT(*) AS  count  FROM usStateCities  GROUP BY state

给出每个州的城市数量

SELECT *
FROM (SELECT state, COUNT(*)  AS count FROM  usstatecities ) AS a,
usstatescentroids b
WHERE a.state = b.state
GROUP BY state

只给出美国的一个州和城市总数我想找到每个州的城市数量和每个州的质心坐标(经度，纬度)。

更正我已将状态更改为状态。我剪切并粘贴了旧语句。

Answer 1

SELECT a.state, a.count, b.lon, b.lat 
FROM (SELECT State, COUNT(*) AS count FROM usStateCities GROUP BY State) a
LEFT JOIN usstatescentroids b ON b.state = a.State