OT: MySQL GROUP_CONCAT Question

Question

Are there any MySQL gurus here who understand MySQL's
GROUP_CONCAT
function? I'm trying to figure out how it works.
This is the query I started with:
$res = mysql_query ("SELECT * FROM cia_ppl CP
LEFT JOIN gw_geog GG on GG.IDArea = CP.ID_Name
LEFT JOIN cia_notes CN on CN.IDName = CP.ID_Name
WHERE CP.Pop != 0") or die (mysql_error());
It works, except that it only displays the first value in
cia_notes.ID_Note in a particular cell. For example, consider
the
following example where there are two notes listed for the
U.S. in table
cia_notes...
ID_Name \ ID_Note
can \ Pop
mex \ Ppl
usa \ Pop
usa \ Ppl
My web page might display the following:
Name \ Population \ Notes
Canada \ 60 million \ Pop
Mexico \ 80 million \ Ppl
United States \ 300 million \ Pop
When I want the last row to look like this:
United States \ 300 million \ PopPpl
I want to use MySQL's SEPARATOR function to insert commas and
a PHP
str_replace to convert it to superscripts, like this:
United States \ 300 million \ 1,2
At any rate, below is the script I came up with to tap into
the
GROUP_CONCAT function. All the data in my table displays
correctly,
except that it now displays no notes (ID_Note) at all. Thanks
for any tips.
SELECT CP.ID
, CP.ID_Name
, CP.Pop
, CP.Pop2
, CP.AgeMed
, CP.Age0
, CP.Age15
, CP.Age65
, CP.Sex
, CP.LifeExp
, CP.PopGrowth
, CP.LitTotal
, GG.IDArea, GG.Name
, DT.ppl_notes
FROM cia_ppl CP
LEFT JOIN gw_geog GG ON GG.IDArea = CP.ID_Name
LEFT OUTER JOIN (
select ID_Name
, GROUP_CONCAT(ID_Note) as ppl_notes
from cia_notes
where Cat = "Ppl"
group
by ID_Name
) as DT
ON DT.ID_Name = CP.ID_Name
WHERE CP.Pop != 0
and CP.ID_Name != 'ear'
AND CP.ID_Name != 'eru'
GROUP BY GG.Name
ORDER BY CP.ID
www.geobop.org - Family Websites
www.invisible-republic.org - Adult political websites (Mature
adults only)

Answer 1

this prod_id to the prim key.
-----------^^
"Field 'prodid' doesn't have a default value"
-------------^
Typo?
Murray --- ICQ 71997575
Adobe Community Expert
(If you *MUST* email me, don't LAUGH when you do so!)
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"Deon H" <[email protected]> wrote in message
news:[email protected]..
> Hi there. (I know this is propably not the right forum
to ask here, but
> the other forums don't help a lot. Please help me.)
>
>
>
> I have been using phpMyAdmin for a couple of years now
and simply love
> it.
> I have just created a new DB with 6 fields of which the
1st one is
> named: prod_id.
> type: smallint
>
> The rest of the fields are the default settings as
usual. I have changed
> this prod_id to the prim key.
>
> For some reason which I cannot figure out why, does not
show under
> "extra" as "auto_increment".
>
> I have double chacked the other db's I have created
exactly as I have
> done this one, and there is says "auto_increment".
> When I now try to add a record to the DB, I get this
error: "Field
> 'prodid' doesn't have a default value"
>
> Please advise where I am doing something wrong.
>
> Sincere regards,
> Deon