Mysql - Counting NULL总是返回0？

Question

我试图得到这个结果：

NULL    350
google  98
yahoo   5
bing    4

使用此查询：

SELECT engine, COUNT(engine) AS count
FROM visits
GROUP BY engine
ORDER BY count DESC

但它返回：

google  98
yahoo   5
bing    4
NULL    0

我该如何解决这个问题？

Answer 1

改为使用COUNT(1)：

SELECT engine, COUNT(1) AS count
FROM visits
GROUP BY engine
ORDER BY count DESC;

• SQL Fiddle Demo