SQL 每列序列

Question

Table

City    Classes
------------------
SCL        X
SCL        Y
SCL        Z
Blah       X
Blah       Y
Narf       X

查询以获得此输出：

City Classes Sequence
SCL     X       1
SCL     Y       2
SCL     Z       3
Blah    X       1
Blah    Y       2
Narf    X       1

有人可以帮助我并告诉我如何实现吗？

Answer 1

SELECT
  City, 
  Classes, 
  row_number() over (partition by City order by classes) Sequence
FROM (values
('SCL','X'),('SCL','Y'),('SCL','Z'),
('Blah','X'),('Blah','Y'),('Narf','X')) x(City, Classes)

结果：

City   Classes  Sequence
Blah   X        1
Blah   Y        2
Narf   X        1
SCL    X        1
SCL    Y        2
SCL    Z        3

SQL 每列序列

SQL Sequence per column

sql-server

count

sequence