[postgis-devel] Re: [postgis-users] how to identify the_geom that cause : RelateOperation called withLWGEOMCOLLECTION type

[Mark Cave-Ayland]

Kevin Neufeld wrote:

> Mark,
> 
> Is it fairly trivial to change the elog in lwgeom_geos.c to your fancy 
> errhint so that when the error is thrown the user has an idea where the 
> problem occurs?

Yeah sure. In fact, elog() has been deprecated for a very long time and 
so in theory we should be using ereport() everywhere.

> The attached patch seems to work, but I got lost when trying to limit 
> the output of the LWGEOMCOLLECTION to the first say 128 characters of 
> the WKT representation.

Yup, code looks good. The only comment is that you want 
PARSER_CHECK_NONE instead of PARSER_CHECK_ALL, otherwise the conversion 
will fail on a non-OGC compliant geometry. So in other words, you only 
really want PARSER_CHECK_ALL on the input/output functions.

In terms of truncating the output, you need to do this manually - see 
http://svn.refractions.net/postgis/trunk/lwgeom/lwgeom_pg.c:pg_parser_errhint 
for the code I used, although if it is needed in multiple places it may 
be a good idea to make this a separate function available in liblwgeom.


HTH,

Mark.

-- 
Mark Cave-Ayland
Sirius Corporation - The Open Source Experts
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