Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people, just like you, are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
Solved

MySQL - help with concat Select statement

Posted on 2011-09-16
4
280 Views
Last Modified: 2012-06-27
I have a table like this:

home_nation        company_nation
CANADA
USA
                             CANADA
                             BERMUDA
                             IRELAND
CANADA              CANADA
                             CANADA
BERMUDA             BERMUDA
BERMUDA
                             USA
BERMUDA
DENMARK             DENMARK

I want to return only unique values from both fields, my current SQL statement looks like this:
SELECT DISTINCT (CONCAT( home_nation, company_nation ))uniqFROM jos_users

Which is very close. It is returning only unique values, but when both fields have a value (like CANADA/CANADA) then the results returned has the country repeated twice, so the current results look like this:

uniq
CANADA
USA
BERMUDA
IRELAND
CANADACANADA
CANADA
BERMUDABERMUDA
DENMARKDENMARK

Is there a way to deal with the double entry problem?

Thanks
     
0
Comment
Question by:elliottbenzle
  • 2
4 Comments
 
LVL 4

Expert Comment

by:ute_arbeit
ID: 36550498
Hi,

if the empty fields are NULL then the statement would be:

SELECT IFNULL(home_nation,company_nation) FROM jos_users;

Cheers
0
 
LVL 52

Expert Comment

by:_agx_
ID: 36552689
IF I'm understanding correctly .. this will return the unique nations in either column

   SELECT DISTINCT home_nation AS uniq  FROM jos_users
   UNION
   SELECT DISTINCT company_nation AS uniq  FROM jos_users

Just exclude the empty values. I'm assuming an empty string.  If not adjust the filter accordingly


SELECT t.Uniq
FROM   (
           SELECT DISTINCT home_nation AS uniq  FROM jos_users
           UNION
           SELECT DISTINCT company_nation AS uniq  FROM jos_users
      ) t
WHERE t.Uniq <> ''



   SELECT DISTINCT home_nation AS uniq  FROM jos_users
   UNION
   SELECT DISTINCT company_nation AS uniq  FROM jos_users
0
 
LVL 52

Accepted Solution

by:
_agx_ earned 500 total points
ID: 36552691
Sorry. ignore the last 3 lines. it's a copy paste error.  The final query is just:

SELECT t.Uniq
FROM   (
           SELECT DISTINCT home_nation AS uniq  FROM jos_users
           UNION
           SELECT DISTINCT company_nation AS uniq  FROM jos_users
      ) t
WHERE t.Uniq <> ''

Open in new window

0
 
LVL 4

Author Closing Comment

by:elliottbenzle
ID: 36564508
Thanks. That was very helpful.
0

Featured Post

Free learning courses: Active Directory Deep Dive

Get a firm grasp on your IT environment when you learn Active Directory best practices with Veeam! Watch all, or choose any amount, of this three-part webinar series to improve your skills. From the basics to virtualization and backup, we got you covered.

Question has a verified solution.

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

Suggested Solutions

Title # Comments Views Activity
How to import sql database into mysql workbench 18 42
AWS EC2 & RDS Instance 5 50
Very Large data in MYSQL 7 73
java mysql insert application 14 25
Foreword In the years since this article was written, numerous hacking attacks have targeted password-protected web sites.  The storage of client passwords has become a subject of much discussion, some of it useful and some of it misguided.  Of cou…
More Fun with XML and MySQL – Parsing Delimited String with a Single SQL Statement Are you ready for another of my SQL tidbits?  Hopefully so, as in this adventure, I will be covering a topic that comes up a lot which is parsing a comma (or other…
Email security requires an ever evolving service that stays up to date with counter-evolving threats. The Email Laundry perform Research and Development to ensure their email security service evolves faster than cyber criminals. We apply our Threat…
With Secure Portal Encryption, the recipient is sent a link to their email address directing them to the email laundry delivery page. From there, the recipient will be required to enter a user name and password to enter the page. Once the recipient …

792 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