Removing Last field from CSV string

Hello,

Perhaps, a statement like :
substring(theString, 1, length(theString)-position(',' IN reverse(theString)))

with theString 'Class V,Class VI,Class VII,Competitive Exam,Class VIII*,Class' for example.
Regards
----- Météo-France -----
PALAYRET JACQUES
DCSC/MBD
jacques.palayret@meteo.fr
Fixe : +33 561078319

On 5/16/20 9:31 AM, PALAYRET Jacques wrote:

Hello,

Perhaps, a statement like :
   substring(theString, 1, length(theString)-position(',' IN
reverse(theString)))

with theString   'Class V,Class VI,Class VII,Competitive Exam,Class
VIII*,Class' for example.

That's cool. I did a little fiddling with above:

SELECT
substring(
left('Class V,Class VI,Class VII,Competitive Exam,Class VIII,Class
X,Class XI,Class IX,Class XII', 60), 1, length(
left('Class V,Class VI,Class VII,Competitive Exam,Class VIII,Class
X,Class XI,Class IX,Class XII', 60)) - position(',' IN reverse(
left('Class V,Class VI,Class VII,Competitive Exam,Class VIII,Class
X,Class XI,Class IX,Class XII', 60))))

substring
--------------------------------------------------------
Class V,Class VI,Class VII,Competitive Exam,Class VIII

Regards
----- Météo-France -----
PALAYRET JACQUES
DCSC/MBD
jacques.palayret@meteo.fr
Fixe : +33 561078319

--
Adrian Klaver
adrian.klaver@aklaver.com

On Sat, May 16, 2020 at 10:19 AM Alex Magnum <magnum11200@gmail.com> wrote:

Hi,

I have a string that I want to cut to 60 char and then remove the last
field and comma.

substring('Class V,Class VI,Class VII,Competitive Exam,Class VIII,Class
X,Class XI,Class IX,Class XII',1,60);

substring | Class V,Class VI,Class VII,Competitive Exam,Class VIII*,Class*

Now I try to remove the last field and comma ",Class"

To get Class V,Class VI,Class VII,Competitive Exam,Class VIII

Is there a function or easy way to do this?
Any help would be appreciated.

You should be able to write a posix patter that does this, you want to
keep everything except a comma followed by 0 or more non-commas and the end
of the string boundary to make sure it gets just the last such match.

--
Mike Nolan
nolan@tssi.com

On 16.05.20 17:18, Alex Magnum wrote:

Now I try to remove the last  field and comma  ",Class"

To get  Class V,Class VI,Class VII,Competitive Exam,Class VIII

Is there a function or easy way to do this?
Any help would be appreciated.

Hi Alex

Many options to do this with regexp_replace, here's one way:

with test as (
select 'Class VII,Competitive Exam,Class VIII,Class' as str
union
select 'Class VIIx,Competitive Exam22,Class VIIIabc,Classx'
)
select str, regexp_replace(str, '^(.*),(.*?)$', '\1') res from test;

|str
|res
|
|------------------------------------------------------|
|Class VII,Competitive Exam,Class VIII,Class
|Class VII,Competitive Exam,Class VIII

|------------------------------------------------------|
|Class VIIx,Competitive Exam22,Class VIIIabc,Classx
|Class VIIx,Competitive Exam22,Class
VIIIabc |

(I cut some columns at the start to better fit email width)

Cheers
Christian

--
Christian Ramseyer, netnea ag
Network Management. Security. OpenSource.
https://www.netnea.com

On Sat, 16 May 2020 23:18:57 +0800
Alex Magnum <magnum11200@gmail.com> wrote:

Hi,

I have a string that I want to cut to 60 char and then remove the last
field and comma.

substring('Class V,Class VI,Class VII,Competitive Exam,Class
VIII,Class X,Class XI,Class IX,Class XII',1,60);

substring | Class V,Class VI,Class VII,Competitive Exam,Class
VIII*,Class*

Now I try to remove the last field and comma ",Class"

To get Class V,Class VI,Class VII,Competitive Exam,Class VIII

Is there a function or easy way to do this?
Any help would be appreciated.

Thank you
Alex

Assuming the CSV strings are in a file, my first thought would be to
get rid of the final field using AWK, and feed that into your import.

SteveT

Steve Litt
May 2020 featured book: Troubleshooting Techniques
of the Successful Technologist
http://www.troubleshooters.com/techniques

Regular expressions, in my opinion, can be a very powerful text search and replace engine if you know how to use it.Feel free to enhance what I provided below; it seems to work for the example you provided.
postgres=# select regexp_replace(substring('Class V,Class VI,Class VII,Competitive Exam,Class VIII,Class X,Class XI,Class IX,Class XII',1,60),'(.*),\w+','\1');                     regexp_replace                     -------------------------------------------------------- Class V,Class VI,Class VII,Competitive Exam,Class VIII(1 row)

Regards,

PflugerGeek
On Saturday, May 16, 2020, 10:19:28 AM CDT, Alex Magnum <magnum11200@gmail.com> wrote:

Hi,
I have a string that I want to cut to 60 char and then remove the last field and comma.

substring('Class V,Class VI,Class VII,Competitive Exam,Class VIII,Class X,Class XI,Class IX,Class XII',1,60);

substring | Class V,Class VI,Class VII,Competitive Exam,Class VIII,Class

Now I try to remove the last  field and comma  ",Class"
To get Class V,Class VI,Class VII,Competitive Exam,Class VIII
Is there a function or easy way to do this?Any help would be appreciated.
Thank youAlex