This works ok 
SELECT round(100 * (ges_kw_zgb / (select sum(ges_kw_zgb) From 
energie.tennet_auswertung_2010)),2) FROM energie.tennet_auswertung_2010


but this does not

update energie.tennet_auswertung_2010 set "Test"=
(
SELECT round(100 * (ges_kw_zgb / (select sum(ges_kw_zgb) From 
energie.tennet_auswertung_2010)),2) FROM energie.tennet_auswertung_2010
);

?????????


________________________________
 Von: Robert Buckley <robertdbuck...@yahoo.com>
An: salah jubeh <s_ju...@yahoo.com>; "pgsql-general@postgresql.org" 
<pgsql-general@postgresql.org> 
Gesendet: 19:30 Montag, 3.September 2012
Betreff: Re: [GENERAL] Create loop in postgresql
 

Now even stranger is that I can´t update a column with the query.

Update energie.tennet_auswertung_2010 set "Test"=(

SELECT round(100*ges_kw_zgb/total.totalsum, 2) from 
energie.tennet_auswertung_2010, 
(select sum(ges_kw_zgb) totalsum From energie.tennet_auswertung_2010) as total
);

ERROR:  more than one row returned by a subquery used as an expression


But If I use Insert as below it DOES work!

insert into energie.tennet_auswertung_2010("Test") SELECT 
round(100*ges_kw_zgb/total.totalsum, 2) 
from energie.tennet_auswertung_2010, (select sum(ges_kw_zgb) totalsum From 
energie.tennet_auswertung_2010) as total;


How would I update the rows?


Cheers for any help,

Rob

________________________________
 Von: salah jubeh <s_ju...@yahoo.com>
An: Robert Buckley <robertdbuck...@yahoo.com>; "pgsql-general@postgresql.org" 
<pgsql-general@postgresql.org> 
Gesendet: 18:23 Montag, 3.September 2012
Betreff: Re: [GENERAL] Create loop in postgresql
 

Hello Robert,

I just gave an example and this also can be optimized . but let me first 
clarify one thing here. 
 
since you have the same behaviour for all values , there is no need to use case 
in the first place. So just drop it.


I think below would be the correct syntax

select name,ges_kw_zgb, (SELECT round(100 * (ges_kw_zgb / (select 
sum(ges_kw_zgb) From energie.tennet_auswertung_2010)),2)) FROM
 energie.tennet_auswertung_2010;


Regards




________________________________
 From: Robert Buckley <robertdbuck...@yahoo.com>
To: salah jubeh <s_ju...@yahoo.com>; "pgsql-general@postgresql.org" 
<pgsql-general@postgresql.org> 
Sent: Monday, September 3, 2012 6:06 PM
Subject: Re: [GENERAL] Create loop in postgresql
 

this give an error.

select name,ges_kw_zgb, SELECT round(100 * (ges_kw_zgb / (select 
sum(ges_kw_zgb) From energie.tennet_auswertung_2010)),2);


ERROR:  syntax error at or near "SELECT"
LINE 2: select name,ges_kw_zgb, SELECT round(100 * (ges_kw_zgb / (se...


________________________________
 Von: salah jubeh <s_ju...@yahoo.com>
An: Robert Buckley <robertdbuck...@yahoo.com>; "pgsql-general@postgresql.org" 
<pgsql-general@postgresql.org> 
Gesendet: 17:45 Montag, 3.September 2012
Betreff: Re: [GENERAL] Create loop in postgresql
 

I am wondering why do not you write it like this 


select name,ges_kw_zgb, select round(100 * (ges_kw_zgb / (select 
sum(ges_kw_zgb) From energie.tennet_auswertung_2010)),2) ...... 


Regards



________________________________
 From: Robert Buckley <robertdbuck...@yahoo.com>
To: "pgsql-general@postgresql.org" <pgsql-general@postgresql.org> 
Sent: Monday, September 3, 2012 5:30 PM
Subject: [GENERAL] Create loop in postgresql
 

Hi,

I am trying to loop through the records in a table and update a column. I can 
do this with a case statement but I would like to simplify this to a simple 
loop statement. I can´t seem to work out how to do it though.

Here is the case statement.

select name,ges_kw_zgb,
case
When name='Bad Harzburg' then (select round(100 * (ges_kw_zgb / (select 
sum(ges_kw_zgb) From energie.tennet_auswertung_2010)),2))
When name='Braunlage' then (select round(100 * (ges_kw_zgb / (select 
sum(ges_kw_zgb) From energie.tennet_auswertung_2010)),2))
When name='Braunschweig' then (select round(100 * (ges_kw_zgb / (select 
sum(ges_kw_zgb) From energie.tennet_auswertung_2010)),2))
When name='Büddenstedt' then (select round(100 * (ges_kw_zgb / (select 
sum(ges_kw_zgb) From energie.tennet_auswertung_2010)),2))

End as z

from energie.tennet_auswertung_2010
;


 Instead of having to write the name variable in the function, I would just 
like to iterate through each record and execute the select round(100 * 
(ges_kw_zgb / (select sum(ges_kw_zgb) From energie.tennet_auswertung_2010)),2) 
command. 


If anyone can help I´d me grateful,

cheers,

Rob

Reply via email to