Thread: need some magic with generate_series()

need some magic with generate_series()

From

Andreas

Date:

23 January 2013, 00:38:37

Hi
I need a series of month numbers like  201212, 201301 YYYYMM to join 
other sources against it.

I've got a table that describes projects:
projects ( id INT, project TEXT, startdate DATE )

and some others that log events
events( project_id INT, createdate DATE, ...)

to show some statistics I have to count events and present it as a view 
with the project name and the month as YYYYMM starting with startdate of 
the projects.

My problem is that there probaply arent any events in a month but I 
still need this line in the output.
So somehow I need to have a select that generates:

project 7,201211
project 7,201212
project 7,201301

It'd be utterly cool to get this for every project in the projects table 
with one select.

Is there hope?

Re: need some magic with generate_series()

From

jan zimmek

Date:

23 January 2013, 00:50:01

hi andreas,

this might give you an idea how to generate series of dates (or other datatypes):

select g, (current_date + (g||' month')::interval)::date from generate_series(1,12) g;

regards
jan

Am 22.01.2013 um 22:41 schrieb Andreas <maps.on@gmx.net>:

> Hi
> I need a series of month numbers like  201212, 201301 YYYYMM to join other sources against it.
>
> I've got a table that describes projects:
> projects ( id INT, project TEXT, startdate DATE )
>
> and some others that log events
> events( project_id INT, createdate DATE, ...)
>
> to show some statistics I have to count events and present it as a view with the project name and the month as YYYYMM
startingwith startdate of the projects. 
>
> My problem is that there probaply arent any events in a month but I still need this line in the output.
> So somehow I need to have a select that generates:
>
> project 7,201211
> project 7,201212
> project 7,201301
>
> It'd be utterly cool to get this for every project in the projects table with one select.
>
> Is there hope?
>
>
> --
> Sent via pgsql-sql mailing list (pgsql-sql@postgresql.org)
> To make changes to your subscription:
> http://www.postgresql.org/mailpref/pgsql-sql

Re: need some magic with generate_series()

From

Filip Rembiałkowski

Date:

23 January 2013, 00:53:14

or even

select m from generate_series( '20121101'::date, '20130101'::date, '1
month'::interval) m;



On Tue, Jan 22, 2013 at 3:49 PM, jan zimmek <jan.zimmek@web.de> wrote:
> hi andreas,
>
> this might give you an idea how to generate series of dates (or other datatypes):
>
> select g, (current_date + (g||' month')::interval)::date from generate_series(1,12) g;
>
> regards
> jan
>
> Am 22.01.2013 um 22:41 schrieb Andreas <maps.on@gmx.net>:
>
>> Hi
>> I need a series of month numbers like  201212, 201301 YYYYMM to join other sources against it.
>>
>> I've got a table that describes projects:
>> projects ( id INT, project TEXT, startdate DATE )
>>
>> and some others that log events
>> events( project_id INT, createdate DATE, ...)
>>
>> to show some statistics I have to count events and present it as a view with the project name and the month as
YYYYMMstarting with startdate of the projects.
 
>>
>> My problem is that there probaply arent any events in a month but I still need this line in the output.
>> So somehow I need to have a select that generates:
>>
>> project 7,201211
>> project 7,201212
>> project 7,201301
>>
>> It'd be utterly cool to get this for every project in the projects table with one select.
>>
>> Is there hope?
>>
>>
>> --
>> Sent via pgsql-sql mailing list (pgsql-sql@postgresql.org)
>> To make changes to your subscription:
>> http://www.postgresql.org/mailpref/pgsql-sql
>
>
>
> --
> Sent via pgsql-sql mailing list (pgsql-sql@postgresql.org)
> To make changes to your subscription:
> http://www.postgresql.org/mailpref/pgsql-sql

Re: need some magic with generate_series()

From

Andreas

Date:

23 January 2013, 01:46:28

Thanks Filip,
with your help I came a step further.   :)

Could I do the folowing without using a function?


CREATE OR REPLACE FUNCTION month_series ( date )  RETURNS table ( monthnr integer )
AS
$BODY$
    select  to_char ( m, 'YYYYMM' )::integer    from    generate_series ( $1, current_date, '1 month'::interval )   
as  m

$BODY$ LANGUAGE sql STABLE;


select  project_id, month_series ( createdate )
from    projects
order by 1, 2;



Am 22.01.2013 22:52, schrieb Filip Rembiałkowski:
> or even
>
> select m from generate_series( '20121101'::date, '20130101'::date, '1
> month'::interval) m;
>
>
>
> On Tue, Jan 22, 2013 at 3:49 PM, jan zimmek <jan.zimmek@web.de> wrote:
>> hi andreas,
>>
>> this might give you an idea how to generate series of dates (or other datatypes):
>>
>> select g, (current_date + (g||' month')::interval)::date from generate_series(1,12) g;
>>
>> regards
>> jan
>>
>> Am 22.01.2013 um 22:41 schrieb Andreas <maps.on@gmx.net>:
>>
>>> Hi
>>> I need a series of month numbers like  201212, 201301 YYYYMM to join other sources against it.
>>>
>>> I've got a table that describes projects:
>>> projects ( id INT, project TEXT, startdate DATE )
>>>
>>> and some others that log events
>>> events( project_id INT, createdate DATE, ...)
>>>
>>> to show some statistics I have to count events and present it as a view with the project name and the month as
YYYYMMstarting with startdate of the projects.
 
>>>
>>> My problem is that there probaply arent any events in a month but I still need this line in the output.
>>> So somehow I need to have a select that generates:
>>>
>>> project 7,201211
>>> project 7,201212
>>> project 7,201301
>>>
>>> It'd be utterly cool to get this for every project in the projects table with one select.
>>>
>>> Is there hope?
>>>
>>>
>>> --
>>> Sent via pgsql-sql mailing list (pgsql-sql@postgresql.org)
>>> To make changes to your subscription:
>>> http://www.postgresql.org/mailpref/pgsql-sql
>>
>>
>> --
>> Sent via pgsql-sql mailing list (pgsql-sql@postgresql.org)
>> To make changes to your subscription:
>> http://www.postgresql.org/mailpref/pgsql-sql