如何计算表中user_id的次数？

Question

Consider the following MySQL table:

user_id
-------
1
1
2
3
3
3
3

I would like an output of:

user_id  cnt
-------------
1        2
2        1
3        4

I though this would make that happen, but it doesn't:

SELECT user_id, COUNT(1) FROM table GROUP BY user_id

What am I doing wrong?

Answer 1

SELECT user_id, COUNT(*) FROM table GROUP BY user_id;

btw, there is also the curiosity:

SELECT user_id, SUM(1) FROM table GROUP BY user_id

Both will give you the output you want.

Answer 2

Try this:

SELECT user_id, COUNT(user_id) as cnt FROM table GROUP BY user_id

Answer 3

SELECT user_id, count(user_id) as total FROM temp group by user_id; 

The query produced this.

user_id  total
-------------
1        2
2        1
3        4