Postgres在WHERE id！= int查询中排除NULL

昨天我在尝试从统计表中过滤出用户ID时遇到了一个Postgres奇怪的问题。例如，当我们执行 user_id！= 24 时，postgres排除了 user_id 为 null 。

I came up against a strange problem in Postgres yesterday when trying to filter out user ids from a stats table. When we did, for example, user_id != 24, postgres excluded the rows where user_id is NULL as well.

我创建了以下测试代码，显示了相同的结果。

I created the following test code which shows the same results.

CREATE TEMPORARY TABLE test1 (
    id int DEFAULT NULL
);

INSERT INTO test1 (id) VALUES (1), (2), (3), (4), (5), (2), (4), (6), 
    (4), (7), (5), (9), (5), (3), (6), (4), (3), (7), 
    (NULL), (NULL), (NULL), (NULL), (NULL), (NULL), (NULL);     

SELECT COUNT(*) FROM test1;

SELECT id, COUNT(*) as count
FROM test1
GROUP BY id;

SELECT id, COUNT(*) as count
FROM test1
WHERE id != 1
GROUP BY id;

SELECT id, COUNT(*) as count
FROM test1
WHERE (id != 1 OR id IS NULL)
GROUP BY id;

第一个查询只计算所有行。
秒计数每个值的数目，包括空值。
第三个排除值1以及所有空值。
第四种方法是排除值1并仍包含空值。

The first query just counts all the rows. The second counts the number of each value, including nulls. The third excludes the value 1 and also all the nulls. The fourth is a work around to exclude value 1 and still include the nulls.

对于我要用于此查询的内容，空值应总是被包括在内。

For what I'm trying to use this query for, null values should always be included.

这是唯一实现此目的的方法吗？这是Postgres的预期行为吗？

Is the work around the only way to do this? Is this expected Postgres behaviour?