Combinar múltiples resultados de consulta en MySQL (por columna)

Question

Tengo 4 consultas diferentes y cada una de ellas devuelve un único conjunto de resultados. Necesito combinar los resultados de la consulta con una sola consulta.

mis consultas de ejemplo son:

1. select cls.* from (calls as cls inner join calls_users as clsusr on cls.id=clsusr.call_id) inner join users as usr on usr.id=cls.assigned_user_id where cls.assigned_user_id='seed_max_id' 

2. select mtn.* from (meetings as mtn inner join meetings_users as mtnusr on mtn.id=mtnusr.meeting_id) inner join users as usr on usr.id=mtn.assigned_user_id where mtn.assigned_user_id='seed_max_id' 

3. select tsk.* from tasks as tsk inner join users as usr on usr.id=tsk.assigned_user_id where tsk.assigned_user_id='seed_max_id' 

4. select nts.* from (notes as nts inner join accounts as acnts on acnts.id=nts.parent_id) inner join users as usr on usr.id=acnts.assigned_user_id where acnts.assigned_user_id='seed_max_id' 

me trataron de la siguiente manera, pero no funcionó

Combine: SELECT tbl1.*, tbl2.* 
from (select cls.* from (calls as cls inner join calls_users as clsusr on cls.id=clsusr.call_id) inner join users as usr on usr.id=cls.assigned_user_id where cls.assigned_user_id='seed_max_id') as tbl1 
left outer join 
(select mtn.* from (meetings as mtn inner join meetings_users as mtnusr on mtn.id=mtnusr.meeting_id) inner join users as usr on usr.id=mtn.assigned_user_id where mtn.assigned_user_id='seed_max_id') as tbl2 
using(assigned_user_id) 

también probé correcta combinación externa y otra interna se une a estoy realmente atascado , si alguien conoce la solución, por favor ayuda. Necesito el resultado similar como How can I join two tables with different number of rows in MySQL?.

Muestra

datos:

De Consulta 1:

+-------------------------------------------+------------------+- 
| Call Name         | Call Description | 
+-------------------------------------------+------------------+- 
| Discuss Review Process     | NULL    | 
| Get More information on the proposed deal | NULL    | 
| Left a message       | NULL    | 
| Discuss Review Process     | NULL    | 
+-------------------------------------------+------------------+ 

De Consulta 2:

+-----------------------+----------------------------------------------------------- 
| Meeting Name   | Meeting Description 
+-----------------------+----------------------------------------------------------- 
| Review needs   | Meeting to discuss project plan and hash out the details o 
| Initial discussion | Meeting to discuss project plan and hash out the details o 
| Demo     | Meeting to discuss project plan and hash out the details o 
| Discuss pricing  | Meeting to discuss project plan and hash out the details o 
| Review needs   | Meeting to discuss project plan and hash out the details o 
+-----------------------+----------------------------------------------------------- 

que necesito para combinar las columnas como la siguiente:

+-------------------------------------------+------------------+-------------------+-------------------+ 
| Call Name         | Call Description |Meeting Name  |Meeting Description| 
+-------------------------------------------+------------------+-------------------+-------------------+ 
| Discuss Review Process     | NULL    |Review needs  |Meeting to discuss | 
| Get More information on the proposed deal | NULL    |Initial discussion |Meeting to discuss | 
| Left a message       | NULL    |Demo    |Meeting to discuss | 
| NULL         | NULL    |Discuss pricing |Meeting to discuss | 
| NULL          | NULL    |Review needs  |Meeting to discuss | 
+-------------------------------------------+------------------+-------------------+-------------------+ 

Answer 1

Lo mejor que puedes hacer es un UNION o UNION ALL, pero esto requiere que tengan el mismo tipo y número de columnas. Por ejemplo:

SELECT 'Customer' AS type, id, name FROM customer 
UNION ALL 
SELECT 'Supplier', id, name FROM supplier 
UNION ALL 
SELECT 'Employee', id, full_name FROM employee 

Los nombres de columna no tienen que coincidir. Los alias de la primera parte se usarán para el resto.

También voy a añadir que en lugar de:

select cls.* from (calls as cls inner join calls_users as clsusr on cls.id=clsusr.call_id) inner join users as usr on usr.id=cls.assigned_user_id where cls.assigned_user_id='seed_max_id' 

debe eliminar la sub consulta innecesaria y sólo hago:

SELECT c.* 
FROM calls c 
JOIN calls_users cu ONc.id = cu.call_id 
WHERE c.assigned_user_id = 'seed_max_id' 

No hay necesidad de que la complejidad adicional y el anterior es eminentemente más legible.

Answer 2

Supongo que quiere que su ejemplo devuelva una sola fila combinando las entradas correspondientes de todas estas tablas. Pruebe esto y díganos si funcionó:

select * from users as usr 
left outer join (calls as cls 
    inner join calls_users as clsusr 
    on cls.id = clsusr.call_id) 
on usr.id = cls.assigned_user_id 

left outer join (meetings as mtn 
    inner join meetings_users as mtnusr 
    on mtn.id = mtnusr.meeting_id) 
on usr.id = mtn.assigned_user_id 

left outer join tasks as tsk 
on usr.id = tsk.assigned_user_id 

left outer join (notes as nts 
    inner join accounts as acnts 
    on acnts.id=nts.parent_id) 
on usr.id = acnts.assigned_user_id 

where user.id = 'seed_max_id'