sql - 缺少列结果(应该很容易修复)

Question

出于某种原因，这只会返回正确的对应城市和国家计数，但拒绝返回国家列。第二列和第三列返回向左移动一位。结果是正确的，只是我调用SELECT country.name时，没有返回这个字段。

SELECT
  country.name,
  city.name,
  COUNT(country_language.language) AS count
FROM
  lab6.country,
  lab6.city,
  lab6.country_language
GROUP BY
  country.name,
  country.country_code,
  country_language.country_code,
  city.name,
  city.id
HAVING
  COUNT(country_language.language) >= 8 AND
  COUNT(country_language.language) <= 12 AND
  country.country_code = country_language.country_code AND
  country.capital = city.id

Answer 1

您很可能需要为其中一个名称列添加别名，如下所示:

SELECT
  country.name,
  city.name as city_name,
  COUNT(country_language.language) AS count
  ...