需要帮助从 mysql 数据库中为摄影项目连接两个表

Question

I am working on a photography project and I am facing a bit issue with joining tables and retrieving data from mysql database. I have created two tables for this project. One table named cm_team is for team members and another table named cm_events for photography events..Assume to shoot a event, we require 6 persons and the id of the person is stored in cm_events table.

As you can see from the above images.. I am storing the id's of members of cm_team in cm_events table.. I wish to obtain the name of the team member in the respective highlighted fields in the cm_events table..Any help is highly appreciated.

for example my desired output should be: instead of 5 under team_lead heading, I should get the name corresponding to 5 ie Arjun

Answer 1

Something like this? (cleaner and faster than subqueries)

 SELECT 
        `event`.client_name,
        `event`.client_number,
        # some more event cols ..
        `team_lead`.`cm_name` AS `team_lead`,
        `candid_photo`.`cm_name` AS `candid_photo`,
        `candid_video`.`cm_name` AS `candid_video`,
        `traditional_photo`.`cm_name` AS `traditional_photo`,
        `traditional_video`.`cm_name` AS `traditional_video`,
        `helper`.`cm_name` AS `helper`
    FROM cm_events `event`
        JOIN cm_team `team_lead` ON `team_lead`.`cm_code` = `event`.`team_lead`
        JOIN cm_team `candid_photo` ON `candid_photo`.`cm_code` = `event`.`candid_photo`
        JOIN cm_team `candid_video` ON `candid_video`.`cm_code` = `event`.`candid_video`
        JOIN cm_team `traditional_photo` ON `traditional_photo`.`cm_code` = `event`.`traditional_photo`
        JOIN cm_team `traditional_video` ON `traditional_video`.`cm_code` = `event`.`traditional_video`
        JOIN cm_team `helper` ON `helper`.`cm_code` = `event`.`helper`
                            

Answer 2

With Sub queries

DROP TABLE IF EXISTS T,t1;
CREATE TABLE T (
id int, name varchar(10));
insert into t values
(1     ,   'aaa'),
(2   ,     'bbb');

create table t1 (
id int, team_lead int,team_a int);
insert into t1 values
(1,1,2),
(2,2,2);

select t1.id, (select t.name from t where t.id = t1.team_lead) team_lead,
(select t.name from t where t.id = t1.team_a) team_a
from t1;

+------+-----------+--------+
| id   | team_lead | team_a |
+------+-----------+--------+
|    1 | aaa       | bbb    |
|    2 | bbb       | bbb    |
+------+-----------+--------+
2 rows in set (0.001 sec)