Mysql join query on three tables with multiple columns

问题

I have three tables like this:

Specialisation

sid | s_name
--------------
 1  | test 1
 2  | test 2

Person

pid | name | sid
------------------
 1  | ABC  |  1
 2  | XYZ  |  2

Timing

tid | time_from | time_to  | pid
----------------------------------
 1  | 08:00:00  | 10:00:00 |  1
 2  | 20:00:00  | 22:00:00 |  1
 3  | 09:00:00  | 14:00:00 |  2
 4  | 19:00:00  | 20:00:00 |  2

**I want to get result something like this*

pid | name | s_name | time_from  | time_to
--------------------------------------------
 1  | ABC  | test 1 | 08:00:00   | 10:00:00

Description:
All three tables are connected.
I want all records where
specialisation id = '1'
person name Like 'ABC'
timing is in between '08:00:00' and '10:00:00'.

I tried several combinations of mysql joins but not able to fetch the data correctly.

回答1:

You can use INNER JOIN for this,

SELECT  a.pid, a.name,
        b.sname,
        c.time_from,
        c.time_to
FROM    person a
        INNER JOIN specialisation b
            ON a.sid = b.sid
        INNER JOIN Timing c
            ON a.pid = c.pid
WHERE   a.sid = 1 and 
        a.name='ABC'  AND 
        c.time_from >= '08:00:00' AND c.time_to <= '10:00:00'

SQLFiddle Demo

回答2:

You can use Simple Join like this

     Select P.pid , name , s_name ,time_from ,
     time_to from Specialisation S 
     Join Person P on P.sid=S.sid 
     Join Timing T on T.pid= P.pid 
     where T.time_from >= '08:00:00' AND T.time_to <='10:00:00' And P.name='ABC';

Fiddle

回答3:

SELECT B.PID pid, B.NAME name, A.SNAME s_name, C.TIME_FROM time_from, C.TIME_TO time_to
FROM SPECIALISATION A, PERSON B, TIMING C
WHERE A.SID = 1 AND A.SID=B.SID AND B.PID=C.PID 
AND C.TIME_FROM >=08:00:00 AND C.TIME_TO <=10.00.00

回答4:

Try :

    SELECT t.pid, p.name, s.s_name, t.time_from, t.time_to 
     FROM   Specialisation AS s
    left join  Person AS p ON p.sid = s.sid
    left join  Timing AS t ON t.pid = p.pid
    WHERE  s.sid = 1
        AND t.time_from >= 08:00:00' AND t.time_to <= 10:00:00
group by t.tid

回答5:

This is a straight forward JOIN with appropriate WHERE condition.

 SELECT t.pid, p.name, s.s_name, t.time_from, t.time_to 
 FROM   Timing AS t
 JOIN   Person AS p ON p.pid = t.pid
 JOIN   Specialisation AS s ON s.sid = p.sid
 WHERE  s.sid = 1
    AND t.time_from >= 08:00:00 AND t.time_to <= 10:00:00

This is a simple condition where you have to use JOINs to fetch data this way. Its so simple that you will get a hang of it right after your first use. May be this question and answers will help you understand it.

回答6:

SELECT p.pid, p.name, s.s_name, t.time_from, t.time_to 
FROM   Timing AS t
JOIN   Person AS p ON p.pid = t.pid
JOIN   specialisation AS s ON s.sid = p.sid
WHERE  s.sid = 1 and p.name='ABC'
AND t.time_from >= '08:00:00' AND t.time_to <= '10:00:00'

来源：https://stackoverflow.com/questions/13302898/mysql-join-query-on-three-tables-with-multiple-columns

标签

mysql

join

relational-database