SQL JOIN 2 filas de la misma tabla

Question

tengo la siguiente tabla:

Name Type  Value 
--------------------- 
mike phone 123  
mike address nyc  
bob address nj  
bob phone 333 

Quiero tener el resultado como este:

name value value 
------------------- 
mike nyc 123 
bob nj  333 

¿Cómo puedo hacerlo?

Answer 1

se llama auto unión. el truco es usar alias.

select 
    address.name, 
    address.value as address, 
    phone.value as phone 
from 
    yourtable as address left join 
    yourtable as phone on address.name = phone.name 
where address.type = 'address' and 
     (phone.type is null or phone.type = 'phone') 

La consulta supone que cada nombre tiene una dirección, pero los números de teléfono son opcionales.

Answer 2

Algo como esto:

SELECT a.name AS name, phone, address 
    FROM (SELECT name, value AS phone FROM mytable WHERE type = "phone") AS a 
    JOIN (SELECT name, value AS address FROM mytable WHERE type = "address") AS b 
    ON(a.name = b.name);