That sounds like a reasonable solution.

Ian

On Thu, 21 May 2020 at 14:40, Andrea Aime <andrea.a...@geo-solutions.it>
wrote:

> Hi,
> following up on this, Even replied to the thread noting that in OGR there
> is no distinction between
> linestring and multilinestring, and that one can force the creation of
> multi geometries by a parameter in ogr2ogr.
>
> Now, that still means many will get it wrong, because they may not be
> aware of the parameter, or aware of the mixed
> single/multi geometries, as long as their tools of choice are based on OGR.
>
> So, while one can be formally "right" about the geopackage being broken,
> I'd still suggest to add a flag forcing
> the store to treat all single geometries as multi ones, and maybe make it
> a default. Most won't even notice and
> will be happy to have the store work with their data, the few that do,
> have a flag to turn off the behavior.
>
> My 2 cents :-)
>
> Cheers
> Andrea
>
> On Thu, May 14, 2020 at 3:15 PM Andrea Aime <andrea.a...@geo-solutions.it>
> wrote:
>
>> Hi all,
>> got confirmation from the spec lead that the GeoPackage is indeed
>> invalid, quoting my question about mixing POLYGON and MULTIPOLYGON in the
>> same table:
>>
>> Andrea,
>> Your instincts are correct here. We're using the simple features rules
>> for geometries and those do not provide a way to classify geometries with a
>> single dimension and unknown multiplicity. In the case you are describing,
>> GEOMETRY should be used. Not doing so violates Requirement 31
>> <http://www.geopackage.org/spec121/#r31>. Perhaps we can update the text
>> to be more explicit about this.
>>
>>
>> Cheers
>> Andrea
>>
>>
>> On Wed, May 13, 2020 at 7:25 PM Jody Garnett <jody.garn...@geocat.net>
>> wrote:
>>
>>> Noted, full table scans on those would not be fun!
>>>
>>> So a warning (or exception?) and a parameter: "force_multi" accepting a
>>> list of tables to multi, or "*" for all of them may be a good combo.
>>>
>>> aside: I wish we had an extra "tab" for the datastores to perform
>>> maintenance activities and checks (and in this case fix the geopackage
>>> definition).
>>> --
>>> Jody Garnett
>>> GeoCat - Government Geographic Data Publishing
>>>
>>>
>>> On Wed, May 13, 2020 at 10:16 AM Andrea Aime <
>>> andrea.a...@geo-solutions.it> wrote:
>>>
>>>> On Wed, May 13, 2020 at 6:57 PM Jody Garnett <jody.garn...@gmail.com>
>>>> wrote:
>>>>
>>>>> Andrea I am personally in favour of throwing an exception if the data
>>>>> is inconsistent, but I respect that some data is not going to be fixed...
>>>>>
>>>>> Would a connection parameter work? Or were you thinking a system
>>>>> property flag ...
>>>>>
>>>>
>>>> Connection parameter, off by default.
>>>>
>>>>
>>>>> Something like "check_geometry_type": do a pass through the geometry
>>>>> to detect this problem and override to MultiPolygon when creating the
>>>>> FeatureType.
>>>>>
>>>>
>>>> Ouch no, this implementation would take forever to run... I'm just
>>>> playing with a couple of Ordnance Survey geopackages, the small one is 
>>>> 10GB,
>>>> the large one over 200GB. There are hundreds of millions of features
>>>> inside, you don't want to actually visit them all to find out that you did
>>>> not really
>>>> need to expand the type ;-)
>>>> Just to give you a reference, here is a summary table for OS mastermap
>>>> topography, full country, single GeoPackage... the largest table has over
>>>> 338 million rows...:
>>>>
>>>>  table_schema |     table_name     | row_estimate |  total  |  index  |   
>>>> toast    |  table  
>>>> --------------+--------------------+--------------+---------+---------+------------+---------
>>>>  translator2  | topographicline    |  338,790,112 | 183 GB  | 42 GB   | 
>>>> 227 MB     | 140 GB translator2  | topographicarea    |  121,382,384 | 101 
>>>> GB  | 14 GB   | 2138 MB    | 85 GB translator2  | cartographictext   |   
>>>> 21,865,014 | 10 GB   | 2695 MB | 8192 bytes | 8022 MB translator2  | 
>>>> topographicpoint   |    4,270,670 | 2015 MB | 453 MB  | 8192 bytes | 1562 
>>>> MB translator2  | cartographicsymbol |    3,705,680 | 1755 MB | 403 MB  | 
>>>> 8192 bytes | 1353 MB translator2  | boundaryline       |      516,863 | 
>>>> 563 MB  | 55 MB   | 24 MB      | 484 MB
>>>>
>>>>
>>>>
>>>>> I considered a flag to force "multi" but that would end up applying to
>>>>> all tables even when it is not needed.
>>>>>
>>>>
>>>> This seems a lot more sane to me... an alternative could be to have the
>>>> user list which tables to "fix", getting a comma
>>>> separated list. A bit more annoying to setup though, could use a
>>>> dedicated UI.
>>>>
>>>> Cheers
>>>> Andrea
>>>>
>>>> == GeoServer Professional Services from the experts! Visit
>>>> http://goo.gl/it488V for more information. == Ing. Andrea Aime
>>>> @geowolf Technical Lead GeoSolutions S.A.S. Via di Montramito 3/A 55054
>>>> Massarosa (LU) phone: +39 0584 962313 fax: +39 0584 1660272 mob: +39 339
>>>> 8844549 http://www.geo-solutions.it http://twitter.com/geosolutions_it
>>>> ------------------------------------------------------- *Con
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>>>>
>>>
>>
>> --
>>
>> Regards, Andrea Aime
>>
>> == GeoServer Professional Services from the experts! Visit
>> http://goo.gl/it488V for more information. == Ing. Andrea Aime @geowolf
>> Technical Lead GeoSolutions S.A.S. Via di Montramito 3/A 55054 Massarosa
>> (LU) phone: +39 0584 962313 fax: +39 0584 1660272 mob: +39 339 8844549
>> http://www.geo-solutions.it http://twitter.com/geosolutions_it
>> ------------------------------------------------------- *Con riferimento
>> alla normativa sul trattamento dei dati personali (Reg. UE 2016/679 -
>> Regolamento generale sulla protezione dei dati “GDPR”), si precisa che ogni
>> circostanza inerente alla presente email (il suo contenuto, gli eventuali
>> allegati, etc.) è un dato la cui conoscenza è riservata al/i solo/i
>> destinatario/i indicati dallo scrivente. Se il messaggio Le è giunto per
>> errore, è tenuta/o a cancellarlo, ogni altra operazione è illecita. Le
>> sarei comunque grato se potesse darmene notizia. This email is intended
>> only for the person or entity to which it is addressed and may contain
>> information that is privileged, confidential or otherwise protected from
>> disclosure. We remind that - as provided by European Regulation 2016/679
>> “GDPR” - copying, dissemination or use of this e-mail or the information
>> herein by anyone other than the intended recipient is prohibited. If you
>> have received this email by mistake, please notify us immediately by
>> telephone or e-mail.*
>>
>
>
> --
>
> Regards, Andrea Aime
>
> == GeoServer Professional Services from the experts! Visit
> http://goo.gl/it488V for more information. == Ing. Andrea Aime @geowolf
> Technical Lead GeoSolutions S.A.S. Via di Montramito 3/A 55054 Massarosa
> (LU) phone: +39 0584 962313 fax: +39 0584 1660272 mob: +39 339 8844549
> http://www.geo-solutions.it http://twitter.com/geosolutions_it
> ------------------------------------------------------- *Con riferimento
> alla normativa sul trattamento dei dati personali (Reg. UE 2016/679 -
> Regolamento generale sulla protezione dei dati “GDPR”), si precisa che ogni
> circostanza inerente alla presente email (il suo contenuto, gli eventuali
> allegati, etc.) è un dato la cui conoscenza è riservata al/i solo/i
> destinatario/i indicati dallo scrivente. Se il messaggio Le è giunto per
> errore, è tenuta/o a cancellarlo, ogni altra operazione è illecita. Le
> sarei comunque grato se potesse darmene notizia. This email is intended
> only for the person or entity to which it is addressed and may contain
> information that is privileged, confidential or otherwise protected from
> disclosure. We remind that - as provided by European Regulation 2016/679
> “GDPR” - copying, dissemination or use of this e-mail or the information
> herein by anyone other than the intended recipient is prohibited. If you
> have received this email by mistake, please notify us immediately by
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-- 
Ian Turton
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