如何枚举SQL中返回的行？

Question

我想知道是否可以枚举返回的行.不是根据任何列内容而是仅产生顺序整数索引.例如

select ?, count(*) as usercount from users group by age

会返回一些东西:

1    12
2    78
3     4
4    42

这是为https://data.stackexchange.com/

Answer 1

尝试:

SELECT
    ROW_NUMBER() OVER(ORDER BY age) AS RowNumber
        ,count(*) as usercount 
    from users 
    group by age

Answer 2

如果是 Oracle，请使用rownum.

SELECT SOMETABLE.*, ROWNUM RN
FROM SOMETABLE
WHERE SOMETABLE.SOMECOLUMN = :SOMEVALUE
ORDER BY SOMETABLE.SOMEOTHERCOLUMN;

最终答案将完全取决于您使用的数据库。