Mysql SQL-尝试关联数据
我只是在学习SQL。我拥有的数据集如下所示:Mysql SQL-尝试关联数据,mysql,sql,Mysql,Sql,我只是在学习SQL。我拥有的数据集如下所示: city_name | work_place_name | min_commute_time | max_commute_time ------------------------------------------------------------------- Austin CONGRESS 25 45 Austin NASA 10
city_name | work_place_name | min_commute_time | max_commute_time
-------------------------------------------------------------------
Austin CONGRESS 25 45
Austin NASA 10 12
Austin CIRCUS 16 35
CEDAR PARK CONGRESS 35 65
CEDAR PARK NASA 28 60
CEDAR PARK CIRCUS 26 55
KYLE CONGRESS 50 85
KYLE NASA 60 100
KYLE CIRCUS 60 100
我正试图找出国会和美国宇航局哪一个城市的最小通勤时间将小于或等于30。我提出了以下查询,但我没有得到我想要的结果
SELECT city_name
FROM commute_times
WHERE min_commute_time<=30 AND (work_place_name='NASA' OR work_place_name='CONGRESS')
我希望的结果是:
City_name
-----------
Austin
你很接近。聚合将填充缺少的部分:
SELECT city_name
FROM commute_times
WHERE min_commute_time <= 30 AND
work_place_name IN ('NASA', 'CONGRESS')
GROUP BY city_name
HAVING COUNT(*) = 2;
选择城市名称
从通勤时间
上下班时间在哪谢谢你,戈登!!
SELECT city_name
FROM commute_times
WHERE min_commute_time <= 30 AND
work_place_name IN ('NASA', 'CONGRESS')
GROUP BY city_name
HAVING COUNT(*) = 2;