Can Inner join be used effeciently with RIGHT or LEFT Join together in single mysql query

Question

I am working on php-mysql script and having two tables namely messages and members. The data in these tables is given below for example:

messages table:

_________________________________________________________________
|m_id| from_id | to_id | msg_subject | msg_body     | sent_time  |
------------------------------------------------------------------
| 1  |    142  |  335  |    hello    |  how are you | 2017-25-10 |
------------------------------------------------------------------
| 2  |    225  |  443  |    hi       |  whats up..  | 2017-26-10 |
------------------------------------------------------------------
| 3  |    332  |  110  |    urgent   |  call me now | 2017-27-10 |
------------------------------------------------------------------

and members table:

______________________________________________________________
| id   | username | f_name  |  l_name   |   city    | gender  |
---------------------------------------------------------------
| 110  |    joe   |  Joe    |    Tom    |  Rome     |    M    |
---------------------------------------------------------------
| 142  |    alb_p |  Albert |    Paul   |  Milan    |    M    |
---------------------------------------------------------------
| 225  |    ruby  |  Ruby   |    Hinge  |  Paris    |    F    |
---------------------------------------------------------------
| 332  |    ram   |  Ram    |    Sharma |  Delhi    |    M    |
---------------------------------------------------------------
| 335  |   kris   |  Kity   |    Krin   |  Milan    |    F    |
---------------------------------------------------------------
| 443  |    reema |  Reema  |    Pink   |  Dubai    |    F    |
---------------------------------------------------------------

Now I want these tables are joined in mysql query in such a way (or use two select in mysql) so that i should get the username, f_name, l_name, city and gender data of for every from_id and to_id. And also I should also get msg_subject,msg_body and sent_time. I am getting this with use of another mysql query in while loop, which I dont want to use because of performance issue for more than 500 rows. Finally I want display the following type of output using html in the web browser:

_____________________________________________________________________________
|m_id|  Message       |   Message      | Message  |   Message    | Msg Sent |
|    | From Member    |   To Member    | Subject  |   Details    |  On Date |    
-----------------------------------------------------------------------------
|    |ID: 142         | ID: 335        |          |              |          |
|    |UserName: alb_p | UserName: kris |          |              |          |
|    |1st Name:Albert | 1st Name: Kity |          |              |          |
| 1  |Last Name: Paul | Last Name: Krin|  hello   | how are you  |2017-25-10|
|    |City: Milan     | City: Milan    |          |              |          |
|    |Gender: Male    | Gender: Female |          |              |          |
-----------------------------------------------------------------------------
|    |ID: 225         | ID: 443        |          |              |          |
|    |UserName: ruby  | UserName:reema |          |              |          |
|    |1st Name:Ruby   | 1st Name:Reema |          |              |          |
| 2  |Last Name:Hinge | Last Name:Pink |  hi      | Whats up..   |2017-26-10|
|    |City: Paris     | City: Dubai    |          |              |          |
|    |Gender: Female  | Gender: Female |          |              |          |
-----------------------------------------------------------------------------

and so on... for m_id row no. 3 also..

I am getting this html table style output as shown above using another mysql query in while loop but i want to achieve this in a single mysql query using double select or two joins. Please suggest me the way and give me that mysql query details.... thanks in advance.. (also to disclose I am just a starter in php-mysql programming..)

Answer 1

Example of using 2 left joins for "from member" and "to member"

select
       m.*, from_men.username, to_mem.username
from messages m
left join members as from_mem on m.from_id = from_mem.id
left join members as to_mem   on m.to_id = to_mem.id