Question

我很难检索数据。

人

PId | Name
---------------
1   | David
2   | Steven
3   | John

PersonDays

PId | Days
---------------
1   | 0
1   | 1
1   | 2
1   | 3
2   | 1
2   | 2
2   | 3
2   | 4
3   | 0
3   | 1
3   | 4

我想从PersonDays表中Day值为1,2,3的人员中检索记录。

所以，大卫和史蒂文是正确的答案。

如何在MySQL中编写查询？

修改

日值是动态的。

Answer 1

select distinct p.* 
from persons p 
     join PersonDays pd on p.PId=pd.PId and pd.Days in (1,2,3)

更新

SELECT p.PId, p.name,COUNT(pd.PId) AS days_count 
FROM Persons p 
INNER JOIN PersonDays pd on p.PId=pd.PId and pd.Days in (1,2,3)
GROUP BY p.PId
HAVING days_count=3

Answer 2

你可以试试这个

select * from Persons where PId  in (
select PId  from PersonDays where Days in (1,2,3)) as P 
where P.PId = Persons.PId;

Answer 3

<强> SQL FIDDLE

<强> QUERY

SELECT p.name AS 'Person Name'
FROM `person` AS p
JOIN (SELECT p.pid AS 'pid',GROUP_CONCAT(pd.days) AS 'days'
FROM `person` AS p
JOIN `persondays` AS pd ON p.pid = pd.pid
GROUP BY p.pid) AS sub ON sub.pid = p.pid
WHERE sub.days LIKE '%1%2%3%'

希望这会对你有帮助......！

在一个表中选择记录，该表必须在另一个表中具有某些行

修改

3 个答案: