MySQL计算所有NULL列

Question

我需要计算并返回MySQL查询中的NULL列数.

SELECT * from posttracks WHERE trackid=100000;

我怎么会列COUNT所有NULL栏目？

编辑:要清楚,我不需要具有空值的行数,我需要行中具有NULL值的列数.

Answer 1

如果我理解你的问题:

SELECT ISNULL(col1) + ISNULL(col2) + ... + ISNULL(col16) AS cnt
FROM yourTable
WHERE trackid=100000

Answer 2

SELECT count(*) from posttracks WHERE Col1 is NULL

Answer 3

SELECT count(*) as amount FROM posttracks WHERE trackid IS NULL GROUP BY trackid;