I’m not sure about SQL/MM. Per https://issues.apache.org/jira/browse/CALCITE-1968 <https://issues.apache.org/jira/browse/CALCITE-1968>, we’ve been aiming to add OpenGIS Simple Feature Access SQL.
I make heavy use of http://www.h2gis.org/docs/dev/home/ <http://www.h2gis.org/docs/dev/home/> to understand what each function does. But we can’t copy code, tests or documentation because h2gis uses LGPL license. We use ESRI internally. They recently changed license to AL, and the community have been helpful when I have questions. Julian > On Mar 21, 2018, at 2:19 AM, johann sorel <[email protected]> wrote: > > Hello Julian, > > I believe the geospatial support you are talking about is based on SQL/MM > right ? > > For now I am just exploring Calcite (a few minutes each time when builds are > running), to see if we can use it's SQL parser and interpretor as an > alternative to OGC Filter/Expression queries. > > Collaboration would be nice, we should start by using the same geometry > objets and library, if calcite has it's own that will be a problem. > > The choice is limited : > > - JTS : https://github.com/locationtech/jts > <https://github.com/locationtech/jts> > > - Esri Geometry : https://github.com/Esri/geometry-api-java > <https://github.com/Esri/geometry-api-java> > > Do you know any other ? > > So far in SIS we didn't choose any library yet because both are limited to > two (and a half) dimensions and their API are completely locked, we can't add > new geometry types or operations. This is going to be a real problem since we > require 3D geometries more and more. > > A idea would be to start a new project at Apache for N dimension geometries > but that won't be me, I don't have the time nor the math skills to do it. > > > Thanks for the links > > Johann > > > On 20/03/2018 18:05, Julian Hyde wrote: >> Johann, >> >> It’s great to meet someone from the SIS project. >> >> As you may know, we have been adding GeoSpatial support for Calcite for a >> while now[1][2][3][4]. We have a GEOMETRY data type and have implemented a >> significant fraction of the OpenGIS SQL function set. The goal is to make >> things work row-at-a-time to start with, but incrementally recognize >> particular patterns that can be written to use particular “spatial indexes”. >> >> I use the term “spatial index” very loosely. It doesn’t have to be an index >> or any particular format. We aim to expose whatever data structures the >> underling engine supports - and even make accelerated spatial queries >> possible on engines without dedicated spatial structures - HBase-style >> key-sorted tables for example. >> >> So, please let us know how we can help with SIS, or if you would like to >> help us build out our Geospatial support. >> >> It looks like your specific questions about adapters are being answered >> elsethread. >> >> Julian >> >> [1] https://issues.apache.org/jira/browse/CALCITE-1968 >> <https://issues.apache.org/jira/browse/CALCITE-1968> >> <https://issues.apache.org/jira/browse/CALCITE-1968 >> <https://issues.apache.org/jira/browse/CALCITE-1968>> >> >> [2] https://issues.apache.org/jira/browse/CALCITE-2031 >> <https://issues.apache.org/jira/browse/CALCITE-2031> >> <https://issues.apache.org/jira/browse/CALCITE-2031 >> <https://issues.apache.org/jira/browse/CALCITE-2031>> >> >> [3] https://issues.apache.org/jira/browse/CALCITE-1861 >> <https://issues.apache.org/jira/browse/CALCITE-1861> >> <https://issues.apache.org/jira/browse/CALCITE-1861 >> <https://issues.apache.org/jira/browse/CALCITE-1861>> >> >> [4] https://issues.apache.org/jira/browse/CALCITE-2160 >> <https://issues.apache.org/jira/browse/CALCITE-2160> >> <https://issues.apache.org/jira/browse/CALCITE-2160 >> <https://issues.apache.org/jira/browse/CALCITE-2160>> >> >>> On Mar 20, 2018, at 4:33 AM, johann sorel <[email protected]> wrote: >>> >>> Hello, >>> >>> A quick presentation since I am new here : >>> My name is Johann Sorel, I am developer (and PMC) on Apache SIS >>> (http://sis.apache.org), and on some others GeotoolKit, Examind, GeoAPI, >>> ...etc... >>> I work mostly on data models and decoder/encoders. >>> >>> >>> I have a few questions on Adaptors to use the SQL capabilities of Calcite >>> in Apache SIS. >>> - Where can we find a up-to-date tutorial or example to execute a basic >>> SELECT query in Java. >>> the short code at >>> https://calcite.apache.org/docs/howto.html#implementing-an-adapter is >>> obsolete with version 1.16. >>> and do not show how we loop on the result records. >>> - The above code use CalcitePrepareImpl which doc says it's for testing >>> purpose and unstable, is there a stable api somewhere ? >>> >>> I'm sorry if those are newbie questions but I could not find the answers in >>> the doc. >>> >>> Thanks >>> >>> Johann Sorel
