Want to protect your cyber security and still get fast solutions? Ask a secure question today.Go Premium

x
?
Solved

how did you hear about us?

Posted on 2013-11-02
3
Medium Priority
?
462 Views
Last Modified: 2013-11-07
I think this question may be related to
http://www.experts-exchange.com/Database/MySQL/Q_28280747.html


I want either the field (profile_id)  or the row of the answer.

CREATE TABLE `a_messages2` (
       `a_messages_id` INT (11) auto_increment  primary key
     , `profile_id` VARCHAR(20)
     , `sender` VARCHAR(20)
     , `message_id` BIGINT (20)
     , `this_user` VARCHAR(20)
     );



INSERT INTO a_messages2
          (`profile_id`, `sender`, `message_id`, `this_user`)
    VALUES
('abl', 'staff3', 3662615602, 'staff3'),
('abl', 'abl', 3660687080, 'staff3'),
('abl', 'staff3', 3658803944, 'staff3'),
('abl', 'staff3', 3649952930, 'staff3'),
('abl', 'staff3', 3644250249, 'staff3'),
('abl', 'staff3', 3614235515, 'staff3'),
('abl', 'abl', 3614140442, 'staff3'),
('abl', 'staff3', 3613984751, 'staff3'),
('abl', 'staff3', 3613936332, 'staff3'),
('abl', 'abl', 3613469574, 'staff3'),
('abl', 'staff3', 3612970481, 'staff3'),
('abl', 'abl', 3609276901, 'staff3'),
('abl', 'abl', 3609276896, 'staff3'),
('abl', 'staff3', 3866086756, 'staff3'),
('abl', 'staff3', 3866079064, 'staff3'),
('abl', 'abl', 3856964132, 'staff3'),
('abl', 'staff3', 3844779912, 'staff3'),
('abl', 'staff3', 3916948647, 'staff3'),
('abl', 'staff3', 3880367425, 'staff3'),
('abl', 'abl', 3977088222, 'staff3'),
('abl', 'staff3', 3974513295, 'staff3'),
('abl', 'staff3', 3973285282, 'staff3'),
('abl', 'abl', 3960907806, 'staff3'),
('abl', 'staff3', 4003664468, 'staff3'),
('abl', 'abl', 4002246444, 'staff3'),
('abl', 'staff3', 3996089944, 'staff3'),
('abl', 'staff3', 4024726432, 'staff3'),
('abl', 'abl', 4021516823, 'staff3'),
('abl', 'staff3', 4018957318, 'staff3'),
('abl', 'abl', 4050609080, 'staff3'),
('abl', 'staff3', 4052368867, 'staff3'),
('abl', 'abl', 4052424820, 'staff3'),
('abl', 'staff3', 4053183569, 'staff3'),
  
('swa','swa','4153199171','staff3'),
('swa','staff3','4150323049','staff3'),
('swa','swa','4146362776','staff3'),
('swa','staff3','4142884979','staff3'),
('swa','staff3','4142884976','staff3')

Open in new window




Real world explanation:
find customers the who messaged us first

Ask them questions such as 'how did you hear about us: radio, tv, internet, friend'

Because these customers did not hear about us from us, because they sent us the first message.


select profile_id, sender,message_id,this_user from a_messages2 where profile_id='abl' order by message_id limit 1

select profile_id, sender,message_id,this_user from a_messages2 where profile_id='swa' order by message_id limit 1

 staff3 sent first message to swa  '4142884976'


abl sent first message to staff3 '3609276896'

there should be results for abl because abl sent first message
but there should be no results for swa, because we sent the first message
0
Comment
Question by:rgb192
  • 2
3 Comments
 
LVL 49

Accepted Solution

by:
PortletPaul earned 2000 total points
ID: 39619770
Locate the minimum message_id per profile_id, match back to messages by message id and then only list those where the sender equals the profile_id
| SENDER | MESSAGE_ID |
|--------|------------|
|    abl | 3609276896 |

Open in new window

produced by the following query:
SELECT
        m.sender
      , m.message_id
FROM (
      SELECT
        profile_id
      , min(message_id) AS message_id
      FROM a_messages2
      GROUP BY
        profile_id
     ) AS mn
INNER JOIN a_messages2 AS m ON mn.message_id =  m.message_id
WHERE m.profile_id = m.sender
;

/* http://sqlfiddle.com/#!9/8efe9/1 */

Open in new window

0
 
LVL 1

Author Closing Comment

by:rgb192
ID: 39619858
You answered the question correctly with the data provided but with my data some profiles I have written first got returned.

So I would want to modify this query to show me more information so I can give you more data.
0
 
LVL 1

Author Comment

by:rgb192
ID: 39631021
0

Featured Post

Free Tool: SSL Checker

Scans your site and returns information about your SSL implementation and certificate. Helpful for debugging and validating your SSL configuration.

One of a set of tools we are providing to everyone as a way of saying thank you for being a part of the community.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Load balancing is the method of dividing the total amount of work performed by one computer between two or more computers. Its aim is to get more work done in the same amount of time, ensuring that all the users get served faster.
The title says it all. Writing any type of PHP Application or API code that provides high throughput, while under a heavy load, seems to be an arcane art form (Black Magic). This article aims to provide some general guidelines for producing this typ…
In this video, Percona Solution Engineer Dimitri Vanoverbeke discusses why you want to use at least three nodes in a database cluster. To discuss how Percona Consulting can help with your design and architecture needs for your database and infras…
In this video, Percona Solution Engineer Rick Golba discuss how (and why) you implement high availability in a database environment. To discuss how Percona Consulting can help with your design and architecture needs for your database and infrastr…
Suggested Courses
Course of the Month13 days, 23 hours left to enroll

580 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question