Re: [JPP-Devel] Perfomance-tips for large vector-layers?
Hi, Thanks Jukka, thanks Martin for your hints. I think I will try to solve some of my problems using postgis-functions like Jukka supposed. If I get round to I will try to deal with JEQL, too. Sounds promisingly. Nils Martin Davis schrieb: Nils, you might try looking at JEQL to do this. http://tsusiatsoftware.net/jeql/main.html It's based on the same geometry library as OJ (JTS), and is probably a little more suited to running batch operations on large datafiles. Feel free to contact me directly for more info. Martin Nils Kuhn wrote: Hi, unfortunatily, I have to work with some very large vector-layers at the moment (more than 800.000 polygons in some shape-files). I have to select features by attribute, write some selections to new layers, union features by attribute, etc. (classical GIS-tasks). That's actually no fun! Has anybody some performance-tips? What's the best data format for working with large vector-layers in OJ? I loaded a polygon-shape to a postGIS-table via shp2pgsql with a spatial index (GIST) but the loaded table doesn's show a better performance than the shape-file (PostgreSQL-Server is located on a windows-server in a local network). Regards, Nils -- This SF.net email is sponsored by Make an app they can't live without Enter the BlackBerry Developer Challenge http://p.sf.net/sfu/RIM-dev2dev ___ Jump-pilot-devel mailing list Jump-pilot-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/jump-pilot-devel -- Dipl.-Biol. Nils Kuhn Email: nils.k...@bws-gmbh.de Fon: +49 (0)40 - 23 16 65-26 Fax: +49 (0)40 - 23 16 65-01 BWS GmbH Gotenstrae 14 D-20097 Hamburg Sitz der Gesellschaft: Hamburg Amtsgericht Hamburg: HRB 87830 Geschftsfhrer: Dipl.-Geol. Robert Dsi Dipl.-Geogr. Hydr. Lutz Krob * HINWEIS: Diese E-Mail und beigefgte Dateien dienen nur der Vorabstimmung und stellen keine rechtswirksame Willenserklrungen oder Beratungsleistungen dar. Es knnen keine Haftungsansprche gegenber der BWS GmbH geltend gemacht werden. Alle rechtswirksamen uerungen (Vertrge, Stellungnahmen, Berechnungen, Vermerke etc.) erhalten Sie von uns in schriftlicher Form und gegebenenfalls auf separatem Datentrger. Wenn Sie nicht der richtige Adressat sind oder diese E-Mail irrtmlich erhalten haben, informieren Sie bitte den Absender und vernichten Sie diese E-Mail. Unerlaubtes Kopieren und Weiterleiten dieser E-Mail sind nicht gestattet. * -- This SF.net email is sponsored by Make an app they can't live without Enter the BlackBerry Developer Challenge http://p.sf.net/sfu/RIM-dev2dev ___ Jump-pilot-devel mailing list Jump-pilot-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/jump-pilot-devel
Re: [JPP-Devel] Perfomance-tips for large vector-layers?
Hi, OpenJUMP is doing all the work in the memory so if you are going to keep all the data open in OpenJUMP then the question is mostly about what is the fastest format to open. Probably shapefiles are. But it is not allways necessary to keep all the data open and for some part of your work PostGIS should do just great. At least select features by attributes and saving the selection to new layers. However, for making select from a database fast you must create also normal indexes for those attributes you are quering. Best performance can often be achieved if you never need to leave PostGIS. For example union by attribute can be performed with plain SQL. See for example http://linfiniti.com/2010/02/dissolving-features-by-an-attribute/ You can still use OpenJUMP for sending SQL through the Run Datastore Query and reading the result from the new union table for checking the results. And naturally creating the new layers from selections, it should go somehow like this create table new_layer as select * from big_table where query_attbibute='my_string'; -Jukka Rahkonen- -Alkuperäinen viesti- Lähettäjä: Nils Kuhn [mailto:nils.k...@bws-gmbh.de] Lähetetty: 18. elokuuta 2010 15:32 Vastaanottaja: OpenJump develop and use Aihe: [JPP-Devel] Perfomance-tips for large vector-layers? Hi, unfortunatily, I have to work with some very large vector-layers at the moment (more than 800.000 polygons in some shape-files). I have to select features by attribute, write some selections to new layers, union features by attribute, etc. (classical GIS-tasks). That's actually no fun! Has anybody some performance-tips? What's the best data format for working with large vector-layers in OJ? I loaded a polygon-shape to a postGIS-table via shp2pgsql with a spatial index (GIST) but the loaded table doesn's show a better performance than the shape-file (PostgreSQL-Server is located on a windows-server in a local network). Regards, Nils -- This SF.net email is sponsored by Make an app they can't live without Enter the BlackBerry Developer Challenge http://p.sf.net/sfu/RIM-dev2dev ___ Jump-pilot-devel mailing list Jump-pilot-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/jump-pilot-devel -- This SF.net email is sponsored by Make an app they can't live without Enter the BlackBerry Developer Challenge http://p.sf.net/sfu/RIM-dev2dev ___ Jump-pilot-devel mailing list Jump-pilot-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/jump-pilot-devel
Re: [JPP-Devel] Perfomance-tips for large vector-layers?
Nils, you might try looking at JEQL to do this. http://tsusiatsoftware.net/jeql/main.html It's based on the same geometry library as OJ (JTS), and is probably a little more suited to running batch operations on large datafiles. Feel free to contact me directly for more info. Martin Nils Kuhn wrote: Hi, unfortunatily, I have to work with some very large vector-layers at the moment (more than 800.000 polygons in some shape-files). I have to select features by attribute, write some selections to new layers, union features by attribute, etc. (classical GIS-tasks). That's actually no fun! Has anybody some performance-tips? What's the best data format for working with large vector-layers in OJ? I loaded a polygon-shape to a postGIS-table via shp2pgsql with a spatial index (GIST) but the loaded table doesn's show a better performance than the shape-file (PostgreSQL-Server is located on a windows-server in a local network). Regards, Nils -- This SF.net email is sponsored by Make an app they can't live without Enter the BlackBerry Developer Challenge http://p.sf.net/sfu/RIM-dev2dev ___ Jump-pilot-devel mailing list Jump-pilot-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/jump-pilot-devel -- Martin Davis Senior Technical Architect Refractions Research, Inc. (250) 383-3022 -- This SF.net email is sponsored by Make an app they can't live without Enter the BlackBerry Developer Challenge http://p.sf.net/sfu/RIM-dev2dev ___ Jump-pilot-devel mailing list Jump-pilot-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/jump-pilot-devel
