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MySQL. Retrieve data from many tables with column in common

I have the following tables in my database.

TABLE_EMPLOYEES
_________________________________________________
| id |   name  |  last name  |       email       |
-------------------------------------------------
|  1 | Henry   | Smith       | henry@gmail.com   |
|  2 | Scarlet | Rogers      | scarlet@gmail.com |
|  3 | John    | Adams       | john@gmail.com    |
=================================================

TABLE_AVATAR

_________________________________
| id | employee_id | avatar_name |
---------------------------------
| 99 | 1           | henry84     |
|100 | 1           | henry84_    |
|101 | 1           | henry84-    |
|442 | 2           | scarlet99   |
|924 | 3           | john-007    |
|926 | 3           | john-008    |
=================================

TABLE_DOCUMENTS

___________________________________
| id | employee_id | document_name |
-----------------------------------
|124 | 2           | cv.doc        |
|125 | 2           | resume.pdf    |
|126 | 2           | scan-01.jpg   |
|127 | 2           | dl.jpg        |
|396 | 3           | cv-john.doc   |
|397 | 3           | scan-2403.jpg |
===================================

My goal is to retrieve all data from all the tables for each employee. TABLE_EMPLOYEES will contain 1 row per record (I need all data), TABLE_AVATAR can hold many rows per record (I only need the newest one (id desc)), and TABLE_DOCUMENTS can hold many rows per record as well as none at all (I need to get all rows per record if any). I know I can join tables by employee_id, but I’m stock getting only one record from TABLE_AVATAR and all records from TABLE_DOCUMENTS.

Any suggestions?

Thanks, Carlos

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Answer

Here I have used GROUP_CONCAT group function to get the document_ids to one column.

    select employee.*,GROUP_CONCAT(documents.document_name)  document_name,(SELECT MAX(id) as avatar_id from zz2  where zz2.employee_id = employee.id ) from zz1 employee LEFT JOIN zz3 documents on documents.employee_id = employee.id  group by employee.id

This will give you the result that is mentioned below.

  id   name   last name   mail                documents            avatar_id
  1   henry    smith     henry@gmail.com          NULL               101
  2   scarlet  rogers    test2@gmail.com   3.jpg,4.jpg,1.jpg,2.jpg   442           
  3   jon      adam      test3@gmail.com     5.jpg,6.jpg             926    

Just replace your table names with zz1,zz2,zz3. I guess this will help you to solve your problem.

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