9. Frequently Asked Question¶

  • What are the differences between QGIS Desktop and QGIS Server?

    QGIS Desktop has a graphical user interface and allows you to create and modify maps. QGIS Server is a server application serving your QGIS project files to end user applications via OGC web services like WMS, WFS, etc..

  • What is OGC?

    The OGC (Open Geospatial Consortium) is an international not for profit organization committed to making quality open standards for the global geospatial community.

  • Name some other web mapping servers?

    ArcGIS server, Geoserver, Mapserver, Mapnik etc.

  • How to compare QGIS server to other web mapping servers? (2021/01/01)

    Features

    QGIS Server

    GeoServer

    ArcGIS Server

    Since

    2006

    2001

    1999

    Licence

    GPL

    GPL

    commercial

    Commercial support

    Multiple companies

    Multiple companies

    ESRI and its vendors network

    Technology

    C++/python

    Java

    C++

    Tile cache

    yes

    yes (via GeoWebCache)

    yes

    3D

    No

    No

    Yes

    Querying

    FES (2.0) and OGC (1.0) filters

    CQL and OGC filters

    OGC filters

    Report generation

    yes

    yes

    yes

    Server administration

    yes via third parties (LizMap, QWC2, etc.)

    web + API REST

    web + API REST

    GIS project Layer/symbology edition

    complete via dedicated GUI

    simple via web interface

    complete via dedicated GUI

  • What are the OGC specification versions implemented in QGIS server compared to other web mapping servers? (2021/01/01)

    OGC standards

    QGIS Server

    GeoServer

    ArcGIS Server

    WMS (Web Map Service)

    1.3.0 - 1.1.1

    1.3.0 - 1.1.1

    1.3.0 - 1.1.1

    WFS (Web Feature Service)

    1.1.0 - 1.0.0

    2.0.0 - 1.0.0

    2.0.0 - 1.0.0

    OAPIF (aka WFS3)

    1.0.0

    no

    no

    WMTS (Web Map Tile Service)

    1.0.0

    1.0.0

    1.0.0

    WCS (Web Coverage Service)

    1.0.0

    2.0.1 - 1.0.0

    2.0.1 - 1.0.0

    WPS (Web Processing Service)

    no

    1.0.0

    1.0.0

    CSW (Catalogue Service for the Web)

    no

    2.0.2

    no

    SLD (Styled Layer Descriptor)

    yes

    yes

    yes

  • What is a tile cache?

    Maps are often static. As most mapping clients render WMS (Web Map Service) data every time they are queried, this can result in unnecessary processing and increased wait times.

    The tile cache optimizes this experience by saving (caching) map images, or tiles, as they are requested, in effect acting as a proxy between client (such as OpenLayers or Google Maps) and server (any WMS-compliant server). As new maps and tiles are requested, QGIS server intercepts these calls and returns pre-rendered tiles if stored, or calls the QGIs engine to render new tiles as necessary. Thus, once tiles are stored, the speed of map rendering increases by many times, creating a much improved user experience.

  • What is PostgreSQL?

    PostgreSQL is a powerful, open source object-relational database companion for QGIS.

  • What is PostGIS?

    PostGIS is a spatial database extender for PostgreSQL object-relational database. It adds support for geographic objects allowing location queries to be run in SQL.

  • To be continued…