Sql选择Distint计数

Question

我有一个有趣的情况，我想用可变值计算DISTINCT行。

想象一下这样的表：

**Customer  City        status**
Acme        Sydney      Exist
Bally       Sydney      new exist
Bally       Melbourne   new exist
Costco      Melbourne   Exist
David       Sydney      null
Ego         Japan       Exist
Dave        Sydney      Exist

我正在寻找这个结果： 按状态分组＆＃34;存在＆＃34;

**City      status**
Sydney      2
Japan       1
Melbourne   1

如何为此结果创建sql查询

谢谢

Answer 1

car_xy =[(650,700),(568,231),(789,123),(968,369)]
car_id =[284,12,466,89]
#required_details merges the two lists
required_details = list(set(car_xy+car_id))
#now if i do print required_details the ouput will be a list like;
required_details = [284,12,(650,700),89,(568,231),466,(968,369),(789,123)] 
#the required details adds the information in list randomly. What if i want  the first elements of both the list together, like
required_details = [[284,(650,700)],[12,(568,231),[466,(789,123)],[89,(968,369)]]

这可能有用。

Answer 2

您正在寻找：

select city, count(*)
from t
where status = 'Exist'
group by city;