php - SQL特定计数查询

Question

"SELECT COUNT (one, two, three, four, five)  FROM $this->tablename where username='$username' and one='Not done' and two='Not done' and three='Not done' and four='Not done' and five='Not done'"

我想计算在“用户名”行的第一、二、三、四和五列中找到“未完成”值的次数。然而，这个查询不起作用。我不知道如何让它工作，但我确实有一种感觉，这个查询可以更短。

Answer 1

试试这个:

SELECT (one='Not done')
     + (two='Not done')
     + (three='Not done')
     + (four='Not done')
     + (five='Not done')
     AS num_not_done
FROM $this->tablename 
where username='$username'

表达式(column='Not did')将返回1或0。因此，您只需将结果相加即可获得匹配项的数量。