[postgis-users] Recursive query - ERROR: invalid memory alloc request size 1073741824

[Shaozhong SHI]

Testing shows that using startnode and endnode of id values of a line does
lead to a fast completion of processing.
However, at the moment, I am not sure whether these startnode (id values)
and endnode (id values) are correct.

I am thinking of generating startnode and endnode values by using
St_startpoint(geom) and ST_endpoint(geom),

And then try out your alternative method for recursive query to see whether
walk the network works.

Is this feasible?

Regards,

David

On Sun, 8 May 2022 at 00:59, Imre Samu <pella.samu at gmail.com> wrote:

> Hi David,
> > There is a loop of recursive query.  It runs at a point where it stops.
> >Can anyone provide pointers how to solve this problem or work around?
>
> Please share "this" recursive query;
>
> My guess:  Probably you have a "forever/endless loop" in your data; *so
> you have to LIMIT the recursive part ;*
>
> related links :
> 1.)  with limiting "depth"   ( where depth < 1000 )
> "Prevent infinite loop in recursive query in Postgresql"
>
> https://stackoverflow.com/questions/51025607/prevent-infinite-loop-in-recursive-query-in-postgresql
> 2.)  with LIMITING clause
> https://www.cybertec-postgresql.com/en/recursive-queries-postgresql/
> *"This example also demonstrates how an endless loop can be avoided with a
> LIMIT clause on the parent query."*
>
> Regards,
>   Imre
>
> Shaozhong SHI <shishaozhong at gmail.com> ezt írta (időpont: 2022. máj. 7.,
> Szo, 15:23):
>
>> There is a loop of recursive query.  It runs at a point where it stops.
>>
>> This error turned up.- ERROR:  invalid memory alloc request size
>> 1073741824
>>
>> Can anyone provide pointers how to solve this problem or work around?
>>
>> Regards,
>>
>> David
>> _______________________________________________
>> postgis-users mailing list
>> postgis-users at lists.osgeo.org
>> https://lists.osgeo.org/mailman/listinfo/postgis-users
>>
> _______________________________________________
> postgis-users mailing list
> postgis-users at lists.osgeo.org
> https://lists.osgeo.org/mailman/listinfo/postgis-users
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.osgeo.org/pipermail/postgis-users/attachments/20220508/a46ffb6b/attachment.htm>