I'm stuck with some tables in mysql. Don't really know how to join the info from three tables. Very thankful if anyone could help me. Thanks.
This is what I have:
Table1.Users
+----+------开发者_运维知识库--+--------------+
| id | name | lastname |
+----+--------+--------------+
| 1 | Peter | Elk |
| 2 | Amy | Lee |
| 3 | James | Ride |
| 4 | Andrea | Thompson |
+----+--------+--------------+
Table2.Projects
+-----+-------------+
| id | name |
+-----+-------------+
| 13 | Lmental |
| 26 | Comunica |
| 28 | Ecobalear |
| 49 | Puigpunyent |
+-----+-------------+
Table3.Users_Projects
+----------+-------------+
| id_users | id_projects |
+----------+-------------+
| 1 | 13 |
| 1 | 28 |
| 2 | 13 |
| 2 | 28 |
| 2 | 49 |
| 3 | 28 |
| 3 | 49 |
| 4 | 49 |
+----------+-------------+
And I would like to print something like this:
+--------+--------------+----------------------------------+
| name | lastname | project |
+--------+--------------+----------------------------------+
| Peter | Elk | Lmental,Ecobalear |
| Amy | Lee | Lmental,Ecobalear, Puigpunyent |
| James | Ride | Ecobalear,Puigounyent |
| Andrea | Thompson | Puigpunyent |
+--------+--------------+----------------------------------+
Something like...
SELECT Users.name, Users.lastname, Projects.name
FROM (Users, Projects, Users_Projects)
WHERE Users_Projects.id_users=Users.id AND Users_Projects.id_projects=Projects.id
ORDER BY ...
...will output a single user/project per line, which you'll then have to manipulate in your choosen language.
Attempting to perform the concatenation, etc. in SQL is liable to lead to a pretty horrendous query.
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