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.. index:: Vector, OGR, Raster, GDAL, Data, Format, QLR

.. index:: PostgreSQL, PostGIS, GeoPackage, SpatiaLite, GRASS, DXF

.. index:: ArcInfo Binary Grid, ArcInfo ASCII Grid, GeoTIFF, Erdas Imagine

Opening Data

.. only:: html

   .. contents::
      :local:

As part of an Open Source Software ecosystem, QGIS is built upon different libraries that, combined with its own providers, offer capabilities to read and often write a lot of formats:

  • Vector data formats include GeoPackage, GML, GeoJSON, GPX, KML, Comma Separated Values, ESRI formats (Shapefile, Geodatabase...), MapInfo and MicroStation file formats, AutoCAD DWG/DXF, GRASS and many more... Read the complete list of supported vector formats.
  • Raster data formats include GeoTIFF, JPEG, ASCII Gridded XYZ, MBTiles, R or Idrisi rasters, GDAL Virtual, SRTM, Sentinel Data, ERDAS IMAGINE, ArcInfo Binary Grid, ArcInfo ASCII Grid, and many more... Read the complete list of supported raster formats.
  • Database formats include PostgreSQL, SQLite/SpatiaLite, Oracle, MS SQL Server, SAP HANA, MySQL...
  • Web map and data services (WM(T)S, WFS, WCS, CSW, XYZ tiles, ArcGIS services, ...) are also handled by QGIS providers. See :ref:`working_with_ogc` for more information about some of these.
  • You can read supported files from archived folders and use QGIS native formats such as QML files (:ref:`qgisstylefile`) and virtual and memory layers.

More than 80 vector and 140 raster formats are supported by GDAL and QGIS native providers.

Note

Not all of the listed formats may work in QGIS for various reasons. For example, some require external proprietary libraries, or the GDAL/OGR installation of your OS may not have been built to support the format you want to use. To see the list of available formats, run the command line ogrinfo --formats (for vector) and gdalinfo --formats (for raster), or check the :menuselection:`Settings --> Options --> GDAL` menu in QGIS.

In QGIS, depending on the data format, there are different tools to open a dataset, mainly available in the :menuselection:`Layer --> Add Layer -->` menu or from the :guilabel:`Manage Layers` toolbar (enabled through :menuselection:`View --> Toolbars` menu). However, all these tools point to a unique dialog, the :guilabel:`Data Source Manager` dialog, that you can open with the dataSourceManager Open Data Source Manager button, available on the :guilabel:`Data Source Manager Toolbar`, or by pressing Ctrl+L. The :guilabel:`Data Source Manager` dialog (:numref:`figure_datasource_manager`) offers a unified interface to open file-based data as well as databases or web services supported by QGIS.

img/datasource_manager.png

QGIS Data Source Manager dialog

Beside this main entry point, you also have the dbManager :guilabel:`DB Manager` plugin that offers advanced capabilities to analyze and manipulate connected databases. More information on DB Manager capabilities can be found in :ref:`dbmanager`.

There are many other tools, native or third-party plugins, that help you open various data formats.

This chapter will describe only the tools provided by default in QGIS for loading data. It will mainly focus on the :guilabel:`Data Source Manager` dialog but more than describing each tab, it will also explore the tools based on the data provider or format specificities.

.. index:: Browse data, Add layers

The Browser Panel

The :guilabel:`Browser` is one of the main ways to quickly and easily add your data to projects. It's available as:

In both cases, the :guilabel:`Browser` helps you navigate in your file system and manage geodata, regardless the type of layer (raster, vector, table), or the datasource format (plain or compressed files, databases, web services).

Exploring the Interface

At the top of the Browser panel, you find some buttons that help you to:

  • addLayer Add Selected Layers: you can also add data to the map canvas by selecting Add selected layer(s) from the layer's context menu;
  • refresh Refresh the browser tree;
  • filterMap Filter Browser to search for specific data. Enter a search word or wildcard and the browser will filter the tree to only show paths to matching DB tables, filenames or folders -- other data or folders won't be displayed. See the Browser Panel(2) example in :numref:`figure_browser_panels`. The comparison can be case-sensitive or not. It can also be set to:
  • collapseTree Collapse All the whole tree;
  • metadata Enable/disable properties widget: when toggled on, a new widget is added at the bottom of the panel showing, if applicable, metadata for the selected item.

The entries in the :guilabel:`Browser` panel are organised hierarchically, and there are several top level entries:

  1. :guilabel:`Favorites` where you can place shortcuts to often used locations
  2. :guilabel:`Spatial Bookmarks` where you can store often used map extents (see :ref:`sec_bookmarks`)
  3. :guilabel:`Project Home`: for a quick access to the folder in which (most of) the data related to your project are stored. The default value is the directory where your project file resides.
  4. :guilabel:`Home` directory in the file system and the filesystem root directory.
  5. Connected local or network drives
  6. Then comes a number of container / database types and service protocols, depending on your platform and underlying libraries:

Interacting with the Browser items

The browser supports drag and drop within the browser, from the browser to the canvas and :guilabel:`Layers` panel, and from the :guilabel:`Layers` panel to layer containers (e.g. GeoPackage) in the browser.

Project file items inside the browser can be expanded, showing the full layer tree (including groups) contained within that project. Project items are treated the same way as any other item in the browser, so they can be dragged and dropped within the browser (for example to copy a layer item to a geopackage file) or added to the current project through drag and drop or double click.

The context menu for an element in the :guilabel:`Browser` panel is opened by right-clicking on it.

For file system directory entries, the context menu offers the following:

For leaf entries that can act as layers in the project, the context menu will have supporting entries. For example, for non-database, non-service-based vector, raster and mesh data sources:

In the :guilabel:`Layer properties` entry, you will find (similar to what you will find in the :ref:`vector <vector_properties_dialog>` and :ref:`raster <raster_properties_dialog>` layer properties once the layers have been added to the project):

Use :guilabel:`Open with Data Source Manager...` to directly open and configure the data source in the :guilabel:`Data Source Manager` using the URI of your data source. This simplifies the process of adding a layer from the :guilabel:`Browser` by allowing you to set specific opening options for the data source. It is currently available for vector (including the dedicated GeoPackage entry), raster, and SpatiaLite data sources.

To add a layer to the project using the :guilabel:`Browser`:

  1. Enable the :guilabel:`Browser` as described above. A browser tree with your file system, databases and web services is displayed. You may need to connect databases and web services before they appear (see dedicated sections).

  2. Find the layer in the list.

  3. Use the context menu, double-click its name, or drag-and-drop it into the :ref:`map canvas <label_mapview>`. Your layer is now added to the :ref:`Layers panel <label_legend>` and can be viewed on the map canvas.

    Tip

    Open a QGIS project directly from the browser

    You can also open a QGIS project directly from the Browser panel by double-clicking its name or by drag-and-drop into the map canvas.

Once a file is loaded, you can zoom around it using the map navigation tools. To change the style of a layer, open the :guilabel:`Layer Properties` dialog by double-clicking on the layer name or by right-clicking on the name in the legend and choosing :menuselection:`Properties` from the context menu. See section :ref:`vector_style_menu` for more information on setting symbology for vector layers.

Right-clicking an item in the browser tree helps you to:

  • for a file or a table, display its metadata or open it in your project. Tables can even be renamed, deleted or truncated.
  • for a folder, bookmark it into your favourites or hide it from the browser tree. Hidden folders can be managed from the :menuselection:`Settings --> Options --> Data Sources` tab.
  • manage your :ref:`spatial bookmarks <sec_bookmarks>`: bookmarks can be created, exported and imported as XML files.
  • create a connection to a database or a web service.
  • refresh, rename or delete a schema.

You can also import files into databases or copy tables from one schema/database to another with a simple drag-and-drop. There is a second browser panel available to avoid long scrolling while dragging. Just select the file and drag-and-drop from one panel to the other.

img/browser_panels.png

QGIS Browser panels side-by-side

Tip

Add layers to QGIS by simple drag-and-drop from your OS file browser

You can also add file(s) to the project by drag-and-dropping them from your operating system file browser to the :guilabel:`Layers Panel` or the map canvas.

.. index:: DB Manager

The DB Manager

The :guilabel:`DB Manager` Plugin is another tool for integrating and managing spatial database formats supported by QGIS (PostgreSQL, SpatiaLite, GeoPackage, Oracle Spatial, MS SQL Server, Virtual layers). It can be activated from the :menuselection:`Plugins --> Manage and Install Plugins...` menu.

The dbManager DB Manager Plugin provides several features:

  • connect to databases and display their structure and contents
  • preview tables of databases
  • add layers to the map canvas, either by double-clicking or drag-and-drop.
  • add layers to a database from the QGIS Browser or from another database
  • create SQL queries and add their output to the map canvas
  • create :ref:`virtual layers <vector_virtual_layers>`

More information on DB Manager capabilities is found in :ref:`dbmanager`.

img/db_manager.png

DB Manager dialog

Provider-based loading tools

Beside the Browser Panel and the DB Manager, the main tools provided by QGIS to add layers, you'll also find tools that are specific to data providers.

Note

Some :ref:`external plugins <plugins>` also provide tools to open specific format files in QGIS.

.. index:: Loading vector, Loading raster

.. index:: ODBC, OGDI, Esri Personal Geodatabase, MySQL

Loading a layer from a file

To load a layer from a file:

  1. Open the layer type tab in the :guilabel:`Data Source Manager` dialog, ie click the dataSourceManager Open Data Source Manager button (or press Ctrl+L) and enable the target tab or:

  2. Check radioButtonOn :guilabel:`File` source type

  3. Click on the :guilabel:`...` Browse button

  4. Navigate the file system and load a supported data source. More than one layer can be loaded at the same time by holding down the Ctrl key and clicking on multiple items in the dialog or holding down the Shift key to select a range of items by clicking on the first and last items in the range. Only formats that have been well tested appear in the formats filter. Other formats can be loaded by selecting All files (the top item in the pull-down menu).

  5. Press :guilabel:`Open` to load the selected file into :guilabel:`Data Source Manager` dialog.

    Depending on the selected layer type, additional :guilabel:`Options` (encoding, geometry type, table filtering, file locking, data formatting ...) are available for configuring. These options are described in detail in the specific GDAL vector or raster driver documentation. At the top of the options, a text with hyperlink will directly lead to the documentation of the appropriate driver for the selected file format.

    img/openoptionsvectorlayer.png

    Loading a Shapefile with open options

  6. Press :guilabel:`Add` to load the file in QGIS and display them in the map view. When adding vector datasets containing multiple layers, the :guilabel:`Select Items to Add` dialog will appear. In this dialog, you can choose the specific layers from your dataset that you want to add. Also, under :guilabel:`Options` you can choose to:

    :numref:`figure_vector_loaded` shows QGIS after loading the :file:`alaska.shp` file.

    img/shapefileloaded.png

    QGIS with Shapefile of Alaska loaded

Note

Because some formats like MapInfo (e.g., :file:`.tab`) or Autocad (:file:`.dxf`) allow mixing different types of geometry in a single file, loading such datasets opens a dialog to select geometries to use in order to have one geometry per layer.

.. index:: ArcInfo Binary Coverage, Tiger Format, UK National Transfer Format

.. index:: US Census Bureau

The addOgrLayer Add Vector Layer and addRasterLayer Add Raster Layer tabs allow loading of layers from source types other than :guilabel:`File`:

Loading a mesh layer

A mesh is an unstructured grid usually with temporal and other components. The spatial component contains a collection of vertices, edges and faces in 2D or 3D space. More information on mesh layers at :ref:`label_meshdata`.

To add a mesh layer to QGIS:

  1. Open the :menuselection:`Data Source Manager` dialog, either by selecting it from the :menuselection:`Layer -->` menu or clicking the dataSourceManager Open Data Source Manager button.
  2. Enable the addMeshLayer :guilabel:`Mesh` tab on the left panel
  3. Press the :guilabel:`...` Browse button to select the file. :ref:`Various formats <mesh_supported_formats>` are supported.
  4. Select the file and press :guilabel:`Add`. The layer will be added using the native mesh rendering.
  5. If the selected file contains many mesh layers, then you'll be prompted with a dialog to choose the sublayers to load. Do your selection and press :guilabel:`OK` and the layers are loaded with the native mesh rendering. It's also possible to load them within a group.
img/mesh_datasource_manager.png

Mesh tab in Data Source Manager

.. index:: CSV, Delimited text files
   see: Comma Separated Values; CSV

Importing a delimited text file

Delimited text files (e.g. :file:`.txt`, :file:`.csv`, :file:`.dat`, :file:`.wkt`) can be loaded using the tools described above. This way, they will show up as simple tables. Sometimes, delimited text files can contain coordinates / geometries that you could want to visualize. This is what addDelimitedTextLayer:guilabel:`Add Delimited Text Layer` is designed for.

  1. Click the dataSourceManager Open Data Source Manager icon to open the :guilabel:`Data Source Manager` dialog
  2. Enable the addDelimitedTextLayer :guilabel:`Delimited Text` tab
  3. Select the delimited text file to import (e.g., :file:`qgis_sample_data/csv/elevp.csv`) by clicking on the :guilabel:`...` Browse button.
  4. Configure the settings to meet your dataset and needs, as explained below.
img/delimited_text_dialog.png

Delimited Text Dialog

File format

Once the file is selected, QGIS attempts to parse the file with the most recently used delimiter, identifying fields and rows. To enable QGIS to correctly parse the file, it is important to select the right delimiter. You can specify a delimiter by choosing between:

Records and fields

Some other convenient options can be used for data recognition:

Field type detection

QGIS tries to detect the field types automatically (unless checkbox:guilabel:`Detect field types` is not checked) by examining the content of an optional sidecar CSVT file (see GeoCSV specification) and by scanning the whole file to make sure that all values can actually be converted without errors, the fall-back field type is text.

The detected field type appears under the field name in sample data preview table and can be manually changed if necessary.

The following field types are supported:

  • Boolean case-insensitive literal couples that are interpreted as boolean values are 1/0, true/false, t/f, yes/no
  • Whole Number (integer)
  • Whole Number (integer - 64 bit)
  • Decimal Number: double precision floating point number
  • Date
  • Time
  • Date and Time
  • Text
Geometry definition

Once the file is parsed, set :guilabel:`Geometry definition` to

Layer settings

Additionally, you can enable:

At the end, click :guilabel:`Add` to add the layer to the map. In our example, a point layer named Elevation is added to the project and behaves like any other map layer in QGIS. This layer is the result of a query on the :file:`.csv` source file (hence, linked to it) and would require :ref:`to be saved <general_saveas>` in order to get a spatial layer on disk.

Sample Data

As you set the parser properties, the sample data preview updates regarding to the applied settings.

Also in the Sample Data Table it is possible to override the automatically determined column types.

Importing a DXF or DWG file

:file:`DXF` and :file:`DWG` files can be added to QGIS by simple drag-and-drop from the Browser Panel. You will be prompted to select the sublayers you would like to add to the project. Layers are added with random style properties.

Note

For DXF files containing several geometry types (point, line and/or polygon), the name of the layers will be generated as <filename.dxf> entities <geometry type>.

To keep the dxf/dwg file structure and its symbology in QGIS, you may want to use the dedicated :menuselection:`Project --> Import/Export --> Import Layers from DWG/DXF...` tool which allows you to:

  1. import elements from the drawing file into a GeoPackage database.
  2. add imported elements to the project.

In the :guilabel:`DWG/DXF Import` dialog, to import the drawing file contents:

  1. Input the location of the :guilabel:`Source drawing`, i.e. the DWG/DXF drawing file to import.
  2. Specify the coordinate reference system of the data in the drawing file.
  3. Input the location of the :guilabel:`Target package`, i.e. the GeoPackage file that will store the data. If an existing file is provided, then it will be overwritten.
  4. Choose how to import blocks with the dedicated combobox:
  5. Check checkbox :guilabel:`Use curves` to promote the imported layers to a curved geometry type.
  6. Use the :guilabel:`Import` button to import the drawing into the destination GeoPackage file. The GeoPackage database will be automatically populated with the drawing file content. Depending on the size of the file, this can take some time.

After the :file:`.dwg` or :file:`.dxf` data has been imported into the GeoPackage database, the frame in the lower half of the dialog is populated with the list of layers from the imported file. There you can select which layers to add to the QGIS project:

  1. At the top, set a :guilabel:`Group name` to group the drawing files in the project. By default this is set to the filename of the source drawing file.
  2. Check layers to show: Each selected layer is added to an ad hoc group which contains vector layers for the point, line, label and area features of the drawing layer. The style of the layers will resemble the look they originally had in *CAD.
  3. Choose if the layer should be visible at opening.
  4. Checking the checkbox :guilabel:`Merge layers` option places all layers in a single group.
  5. Press :guilabel:`OK` to open the layers in QGIS.
img/dwg_dxf_import_dialog.png

Import dialog for DWG/DXF files

.. index:: OSM (OpenStreetMap)

Importing OpenStreetMap Vectors

The OpenStreetMap project is popular because in many countries no free geodata such as digital road maps are available. The objective of the OSM project is to create a free editable map of the world from GPS data, aerial photography and local knowledge. To support this objective, QGIS provides support for OSM data.

Using the :guilabel:`Browser Panel`, you can load an :file:`.osm` file to the map canvas, in which case you'll get a dialog to select sublayers based on the geometry type. The loaded layers will contain all the data of that geometry type in the :file:`.osm` file, and keep the :file:`osm` file data structure.

.. index::
   pair: SpatiaLite; SQLite

SpatiaLite Layers

addSpatiaLiteLayer The first time you load data from a SpatiaLite database, begin by:

This will bring up a window that will allow you either to connect to a SpatiaLite database already known to QGIS (which you choose from the drop-down menu) or to define a new connection to a new database. To define a new connection, click on :guilabel:`New` and use the file browser to point to your SpatiaLite database, which is a file with a :file:`.sqlite` extension.

QGIS also supports editable views in SpatiaLite.

GPS

There are dozens of different file formats for storing GPS data. The format that QGIS uses is called GPX (GPS eXchange format), which is a standard interchange format that can contain any number of waypoints, routes and tracks in the same file.

Use the :guilabel:`...` Browse button to select the GPX file, then use the check boxes to select the feature types you want to load from that GPX file. Each feature type will be loaded in a separate layer.

More on GPS data manipulation at :ref:`working_gps`.

img/gps_datasource.png

Loading GPS Data dialog

GRASS

Working with GRASS vector data is described in section :ref:`sec_grass`.

.. index:: Database tools, MSSQL Spatial

Database related tools

.. index:: Database; Connecting
Creating a stored Connection

In order to read and write tables from a database format QGIS supports you have to create a connection to that database. While :ref:`QGIS Browser Panel <browser_panel>` is the simplest and recommended way to connect to and use databases, QGIS provides other tools to connect to each of them and load their tables:

These tools are accessible either from the :guilabel:`Manage Layers Toolbar` and the :menuselection:`Layer --> Add Layer -->` menu. Connecting to SpatiaLite database is described at :ref:`label_spatialite`.

Tip

Create connection to database from the QGIS Browser Panel

Selecting the corresponding database format in the Browser tree, right-clicking and choosing connect will provide you with the database connection dialog.

Most of the connection dialogs follow a common structure:

  • a section with credentials information to connect to the database
  • a section with options to tune which data can be requested in the database
Connecting to PostgreSQL

The first time you use a PostgreSQL data source, you must create a connection to a database that contains the data. Press the appropriate button as exposed above, opening the :guilabel:`PostgreSQL` tab of the :guilabel:`Data Source Manager` dialog. To access the connection manager, click on the :guilabel:`New` button to display the :guilabel:`Create a New PostgreSQL Connection` dialog.

img/newpostgisconnection.png

Create a New PostgreSQL Connection Dialog

  • :guilabel:`Name`: A name for this connection. It can be the same as :guilabel:`Database`.
  • :guilabel:`Service`: Service parameter to be used alternatively to hostname/port (and potentially database). This can be defined in :file:`pg_service.conf`. Check the :ref:`PostgreSQL Service connection file <pg-service-file>` section for more details.
  • :guilabel:`Host`: Name of the database host. This must be a resolvable host name such as would be used to open a TCP/IP connection or ping the host. If the database is on the same computer as QGIS, simply enter localhost here.
  • :guilabel:`Port`: Port number the PostgreSQL database server listens on. The default port for PostgreSQL is 5432.
  • :guilabel:`Database`: Name of the database.
  • :guilabel:`SSL mode`: SSL encryption setup. The following options are available:
    • :guilabel:`Prefer` (the default): I don't care about encryption, but I wish to pay the overhead of encryption if the server supports it.
    • :guilabel:`Require`: I want my data to be encrypted, and I accept the overhead. I trust that the network will make sure I always connect to the server I want.
    • :guilabel:`Verify CA`: I want my data encrypted, and I accept the overhead. I want to be sure that I connect to a server that I trust.
    • :guilabel:`Verify Full`: I want my data encrypted, and I accept the overhead. I want to be sure that I connect to a server I trust, and that it's the one I specify.
    • :guilabel:`Allow`: I don't care about security, but I will pay the overhead of encryption if the server insists on it.
    • :guilabel:`Disable`: I don't care about security, and I don't want to pay the overhead of encryption.
  • :guilabel:`Session role`: used to set the current user identifier of the current session. This is useful to automatically give the ownership of a new object (table, view, function) to the session_role group and thus share ownership and associated rights with all members of the session_role group. Read more about session role.
  • :guilabel:`Authentication`: For general details about the authentication dialog behavior, see :ref:`authentication`.

Optionally, depending on the type of database, you can activate the following checkboxes:

Once all parameters and options are set, you can test the connection by clicking the :guilabel:`Test Connection` button or apply it by clicking the :guilabel:`OK` button.

PostgreSQL Service connection file

The service connection file allows PostgreSQL connection parameters to be associated with a single service name. That service name can then be specified by a client and the associated settings will be used.

It's called :file:`.pg_service.conf` under *nix systems (GNU/Linux, macOS etc.) and :file:`pg_service.conf` on Windows.

The service file can look like this:

[water_service]
host=192.168.0.45
port=5433
dbname=gisdb
user=paul
password=paulspass

[wastewater_service]
host=dbserver.com
dbname=water
user=waterpass

Note

There are two services in the above example: water_service and wastewater_service. You can use these to connect from QGIS, pgAdmin, etc. by specifying only the name of the service you want to connect to (without the enclosing brackets). If you want to use the service with psql, you can do psql service=water_service.

You can find all the PostgreSQL parameters here

Note

If you don't want to save the passwords in the service file you can use the .pg_pass option.

Note

QGIS Server and service

When using a service file and QGIS Server, you must configure the service on the server side as well. You can follow the :ref:`QGIS Server <QGIS-Server-manual>` documentation.

On *nix operating systems (GNU/Linux, macOS etc.) you can save the :file:`.pg_service.conf` file in the user's home directory and PostgreSQL clients will automatically be aware of it. For example, if the logged user is web, :file:`.pg_service.conf` should be saved in the :file:`/home/web/` directory in order to directly work (without specifying any other environment variables).

You can specify the location of the service file by creating a PGSERVICEFILE environment variable (e.g. run the export PGSERVICEFILE=/home/web/.pg_service.conf command under your *nix OS to temporarily set the PGSERVICEFILE variable).

You can also make the service file available system-wide (all users) either by placing the :file:`.pg_service.conf` file in pg_config --sysconfdir or by adding the PGSYSCONFDIR environment variable to specify the directory containing the service file. If service definitions with the same name exist in the user and the system file, the user file takes precedence.

Warning

There are some caveats under Windows:

Connecting to Oracle Spatial
img/neworacleconnection.png

Create a New Oracle Connection Dialog

The spatial features in Oracle Spatial aid users in managing geographic and location data in a native type within an Oracle database. The connection dialog proposes:

Optionally, you can activate the following checkboxes:

Tip

Oracle Spatial Layers

Normally, an Oracle Spatial layer is defined by an entry in the USER_SDO_METADATA table.

To ensure that selection tools work correctly, it is recommended that your tables have a primary key.

Connecting to MS SQL Server

As mentioned in :ref:`vector_create_stored_connection` QGIS allows you to create MS SQL Server connection through :guilabel:`Data Source Manager`.

img/mssql_connection_dialog.png

MS SQL Server Connection

To create a new MS SQL Server connection, you need to provide some of the following information in the :guilabel:`Connection Details` dialog:

Navigate to the :guilabel:`Database Details` section and click the :guilabel:`List Databases` button to view the available datasets. Select datasets that you want, then press :guilabel:`OK`. Optionally, you can also perform a :guilabel:`Test Connection`. Once you click :guilabel:`OK` the :guilabel:`Create a New MS SQL Server Connection` dialog will close and in the :guilabel:`Data Source Manager` press :guilabel:`Connect`, select a layer and then click :guilabel:`Add`.

Optionally, you can activate the following options:

  • checkbox :guilabel:`Only look in the geometry_columns metadata table`: restricts the available tables to the ones in the geometry_columns metadata table when scanning for tables. This can speed up the table scanning.
  • checkbox :guilabel:`Use layer extent from geometry_columns table`: this option, dependent on the previous one, allows QGIS to skip extent calculation when loading layers and thus lowering the amount of time needed to load them. It relies on extent manually specified using additional QGIS-specific columns (qgis_xmin, qgis_xmax, qgis_ymin, qgis_ymax) in the geometry_columns table.
  • checkbox :guilabel:`Use primary key from geometry_columns table`: allows QGIS to skip primary key calculation for views when loading them, thus lowering the amount of time needed to load them. It relies on names manually filled in a QGIS-specific qgis_pkey column set in the geometry_columns table. If more than one column is used for the primary key, they should be filled as comma separated values.
  • checkbox :guilabel:`Also list table with no geometry`: tables without a geometry column attached will also be shown in the available table list.
  • checkbox :guilabel:`Use estimated table parameters`: only estimated table metadata will be used. This avoids a slow table scan, but may result in incorrect layer properties such as layer extent.
  • checkbox :guilabel:`Skip invalid geometry handling`: all handling of records with invalid geometry will be disabled. This speeds up the provider, however, if any invalid geometries are present in a table then the result is unpredictable and may include missing records. Only check this option if you are certain that all geometries present in the database are valid, and any newly added geometries or tables will also be valid.
  • checkbox :guilabel:`Use only a Subset of Schemas` will allow you to filter schemas for MS SQL connection. If enabled, only checked schemas will be displayed. You can right-click to :guilabel:`Check` or :guilabel:`Uncheck` any schema in the list.
Renaming a Vector Table (MS SQL)
Connecting to SAP HANA

Note

You require the SAP HANA Client to connect to a SAP HANA database. You can download the SAP HANA Client for your platform at the SAP Development Tools website.

img/newhanaconnection.png

Create a New SAP HANA Connection Dialog

The following parameters can be entered:

Tip

Connecting to SAP HANA Cloud

If you'd like to connect to an SAP HANA Cloud instance, you usually must set :guilabel:`Port Number` to 443 and check :guilabel:`Enable TLS/SSL encryption`.

Loading a Database Layer

Once you have one or more connections defined to a database (see section :ref:`vector_create_stored_connection`), you can load layers from it. Of course, this requires that data are available. See section :ref:`vector_import_data_in_postgis` for a discussion on importing data into a PostgreSQL database.

To load a layer from a database, you can perform the following steps:

  1. Open the corresponding tab of the database in the :guilabel:`Data Source Manager` dialog.

  2. Choose the connection name from the drop-down list and press :guilabel:`Connect`.

  3. The table below will be filled with your data grouped by schema, with a number of metadata information helpful for loading.

  4. Select or unselect checkbox :guilabel:`Also list tables with no geometry`.

  5. Optionally, use some checkbox :guilabel:`Search Options` to reduce the list of tables to those matching your search. You can also set this option before you hit the :guilabel:`Connect` button, speeding up the database fetching.

  6. Find the layer(s) you wish to add in the list of available layers.

  7. Select it by clicking on it. You can select multiple layers by holding down the Shift or Ctrl key while clicking.

    Layers can be selected only if they have no warning warning icon at the left-hand side of their first column. This may indicate an issue to detect:

    • features geometry type: in which case you can select the appropriate one in the drop-down list of the :guilabel:`Spatial Type` column

    • layer CRS: you can enter the correct code in the :guilabel:`SRID` column

    • layer's primary key, in order to unequivocally identify each feature: this can be fixed by selecting one or more attributes in the drop-down list at the corresponding :guilabel:`Feature id` column.

      Tip

      Use the first column to store "primary keys" for views

      Since PostgreSQL views don't support primary keys, a unique attribute or combination of attributes should always be selected. To help users to speed-up workflows, QGIS automatically selects the first attribute in the view. Therefore, users can define their views in a way that a unique column is in the first position of the view's definition. In this way, the view will be loaded with no extra interaction and the warning icon will never appear.

  8. If applicable, use the :guilabel:`Set Filter` button (or double-click the layer) to start the :guilabel:`Query Builder` dialog (see section :ref:`vector_query_builder`) and define which features to load from the selected layer. The filter expression appears in the sql column. This restriction can be removed or edited in the :menuselection:`Layer Properties --> General --> Provider Feature Filter` frame.

  9. The checkbox in the Select at id column that is activated by default gets the feature ids without the attributes and generally speeds up the data loading.

  10. Click on the :guilabel:`Add` button to add the layer to the map.

img/addpostgistables.png

Add PostgreSQL Table(s) Dialog

Tip

Use the Browser Panel to speed up loading of database table(s)

Adding DB tables from the :guilabel:`Data Source Manager` may sometimes be time consuming as QGIS fetches statistics and properties (e.g. geometry type and field, CRS, number of features) for each table beforehand. To avoid this, once :ref:`the connection is set <vector_create_stored_connection>`, it is better to use the :ref:`Browser Panel <browser_panel>` or the :ref:`DB Manager <dbmanager>` to drag and drop the database tables into the map canvas.

The Layer Metadata Search Panel

By default, QGIS can retrieve layers metadata from the connections or data providers that allow metadata storage (more details on :ref:`saving metadata to the database <savemetadatatodb>`). The :guilabel:`Metadata search` panel allows to browse the layers by their metadata and add them to the project (either with a double-click or the :guilabel:`Add` button). The list can be filtered:

Note

The sources of metadata are implemented through a layer metadata provider system that can be extended by plugins.

img/layer_metadata_search_panel.png

Layer Metadata Search Panel

QGIS Custom formats

QGIS proposes two custom formats:

.. index:: QGIS Layer Definition File, QLR file

QLR - QGIS Layer Definition File

Layer definitions can be saved as a :ref:`Layer Definition File <qgislayerdefinitionfile>` (QLR - :file:`.qlr`) using :menuselection:`Export --> Save As Layer Definition File...` in the layer context menu.

The QLR format makes it possible to share "complete" QGIS layers with other QGIS users. QLR files contain links to the data sources and all the QGIS style information necessary to style the layer.

QLR files are shown in the Browser Panel and can be used to add layers (with their saved styles) to the Layers Panel. You can also drag and drop QLR files from the system file manager into the map canvas.

Available actions for QLR files in the Browser Panel are:

Connecting to web services

With QGIS you can get access to different types of OGC web services (WM(T)S, WFS(-T), WCS, CSW, ...). Thanks to QGIS Server, you can also publish such services. :ref:`QGIS-Server-manual` contains descriptions of these capabilities.

.. index:: Vector Tiles services

Using Vector Tiles services

Vector Tile services can be added via the addVectorTileLayer :guilabel:`Vector Tiles` tab of the :guilabel:`Data Source Manager` dialog or the contextual menu of the :guilabel:`Vector Tiles` entry in the :guilabel:`Browser` panel. Services can be either a :guilabel:`New Generic Connection...` or a :guilabel:`New ArcGIS Vector Tile Service Connection...`.

You set up a service by adding:

  • a :guilabel:`Name`

  • a :guilabel:`Style URL`: a URL to a MapBox GL JSON style configuration. If provided, then that style will be applied whenever the layers from the connection are added to QGIS. In the case of Arcgis vector tile service connections, the URL overrides the default style configuration specified in the server configuration.

    You can load vector tiles directly from a :guilabel:`Style URL`. The data source is automatically parsed from the style, and URLs with multiple sources are supported. That makes :guilabel:`Source URL` optional.

  • the :guilabel:`Source URL`: of the type http://example.com/{z}/{x}/{y}.pbf for generic services and http://example.com/arcgis/rest/services/Layer/VectorTileServer for ArcGIS based services. The service must provide tiles in :file:`.pbf` format.

  • the checkbox:guilabel:`Min. Zoom Level` and the checkbox:guilabel:`Max. Zoom Level`. Vector Tiles have a pyramid structure. By using these options you have the opportunity to individually generate layers from the tile pyramid. These layers will then be used to render the Vector Tile in QGIS.

    For Mercator projection (used by OpenStreetMap Vector Tiles) Zoom Level 0 represents the whole world at a scale of 1:500.000.000. Zoom Level 14 represents the scale 1:35.000.

  • the :ref:`authentication <authentication>` configuration if necessary

  • a :guilabel:`Referer`

:numref:`figure_vector_tiles_configuration` shows the dialog with the Vector Tiles service configuration.

img/vector_tiles_configuration.png

Vector Tiles - Service configuration

Configurations can be saved to :file:`.XML` file (:guilabel:`Save Connections`) through the :guilabel:`Vector Tiles` entry in :guilabel:`Data Source Manager` dialog or its context menu in the :guilabel:`Browser` panel. Likewise, they can be added from a file (:guilabel:`Load Connections`).

Once a connection to a vector tile service is set, it's possible to:

.. index:: XYZ Tile services

Using XYZ Tile services

XYZ Tile services can be added via the addXyzLayer :guilabel:`XYZ` tab of the :guilabel:`Data Source Manager` dialog or the contextual menu of the :guilabel:`XYZ Tiles` entry in the :guilabel:`Browser` panel. By default, QGIS provides some default and ready-to-use XYZ Tiles services:

To add a new service, press :guilabel:`New` (respectively :guilabel:`New Connection` from the Browser panel) and provide:

img/xyz_tiles_dialog_osm.png

XYZ Tiles - OpenStreetMap configuration

Press :guilabel:`OK` to establish the connection. It will then be possible to:

Configurations can be saved to :file:`.XML` file (:guilabel:`Save Connections`) through the :guilabel:`XYZ` entry in :guilabel:`Data Source Manager` dialog or its contextual menu in the :guilabel:`Browser` panel. Likewise, they can be added from a file (:guilabel:`Load Connections`).

The XML file for OpenStreetMap looks like this:

<!DOCTYPE connections>
<qgsXYZTilesConnections version="1.0">
  <xyztiles url="https://tile.openstreetmap.org/{z}/{x}/{y}.png"
   zmin="0" zmax="19" tilePixelRatio="0" password="" name="OpenStreetMap"
   username="" authcfg="" referer=""/>
</qgsXYZTilesConnections>

Tip

Loading XYZ tiles without creating a connection

It is also possible to add XYZ tiles to a project without necessarily storing its connection settings in you user profile (e.g. for a dataset you may need once). In the :menuselection:`Data Source Manager --> XYZ` tab, edit any properties in the :guilabel:`Connection Details` group. The :guilabel:`Name` field above should turn into Custom. Press :guilabel:`Add` to load the layer in the project. It will be named by default XYZ Layer.

Examples of XYZ Tile services:

.. index:: ArcGIS REST Servers

Using ArcGIS REST Servers

An ArcGIS REST Server can host many different types of web services (feature service, map service, image service, ...). ArcGIS REST Servers can be added via the addAfsLayer :guilabel:`ArcGIS REST Server` tab of the :guilabel:`Data Source Manager` dialog or the contextual menu of the :guilabel:`ArcGIS REST Servers` entry in the :guilabel:`Browser` panel:

  1. Press :guilabel:`New` (respectively :guilabel:`New Connection`) and provide:

    Note

    ArcGIS Feature Service connections which have their corresponding Portal endpoint URLS set can be explored by content groups in the browser panel.

    If a connection has the Portal endpoints set, then expanding out the connection in the browser will show a “Groups” and “Services” folder, instead of the full list of services usually shown. Expanding out the groups folder will show a list of all content groups that the user is a member of, each of which can be expanded to show the service items belonging to that group.

  2. Then press :guilabel:`OK` to validate the configuration settings. These configurations can be saved to :file:`.XML` file (:guilabel:`Save`). Likewise, they can be added from a file (:guilabel:`Load`).

  3. Once a connection to an ArcGIS REST Server is set, it is possible to:

  4. Press :guilabel:`Connect` to request the server and display its contents. They are organized in a tree structure whose nodes depend on the connection's endpoint.

    img/arcgis_rest_server.png

    Data Source Manager - ArcGIS REST Server

  5. Expand the tree to find and select the layers of interest. Their :guilabel:`Coordinate Reference System` is displayed at the bottom of the dialog.

  6. For raster-based layers, you can select the :guilabel:`Image encoding` to use among a number of image formats advertised by the target service ( e.g., PNG, JPG, GIF, SVG, SVGZ, ... ).

  7. To add the selected layers to the map canvas, press :guilabel:`Add` button.

    Because layers can sometimes load and render slowly on the client side, applying a filter to restrict the features retrieved from the service can significantly improve performance, since only the filtered features are requested from the server. This can be done by:

Most of the above tools to connect and access layers on an ArcGIS REST Server are also available from the :guilabel:`Browser` panel, within the contextual menu of the target node item. Depending on the node, you can also:

  • :guilabel:`View Service Info` which will open the default web browser and display information on the requested service.
  • View the :guilabel:`Layer Properties...` and get access to the metadata and a preview of the data provided by the service. More settings are available when the layer has been loaded into the project.
.. index:: 3D Tiles services

Using 3D tiled scene services

QGIS supports multiple formats of 3D tiled datasets, grouped together as "tiled scenes". These include Cesium 3D Tiles and Quantized Mesh tiles.

To load a tiled scene dataset into QGIS, use the addTiledSceneLayer :guilabel:`Scene` tab in the :guilabel:`Data Source Manager` dialog.

img/scene.png

Data Source Manager - Scene

Create a connection by clicking on :guilabel:`New`. You can add a :guilabel:`New Cesium 3D Tiles Connection` or a :guilabel:`New Quantized Mesh Connection`.

Choose a :guilabel:`Name` and set the :guilabel:`URL` to the URL of a layer description JSON file.

The URL may be remote (e.g. http://example.com/tileset.json) or local (e.g. file:///path/to/tiles/tileset.json).

The :ref:`authentication <authentication>` configuration if necessary.

img/tiled_scene_connection.png

Tiled Scene Connection

You can also add the service from :guilabel:`Browser Panel`.

After creating new connection you are able to :guilabel:`Add` the new layer to your map.

img/3d_tiles_layer.png

3D Tiles Layer - Textured

img/quantized_mesh_layer.png

Quantized Mesh layer

.. index:: Cloud connections

Using Cloud Connections

QGIS supports connections to cloud services like Alibaba Cloud OSS, Amazon S3, Google Cloud Storage, Microsoft Azure Blob Storage, Microsoft Azure Data Lake Storage, and OpenStack Swift Object Storage. You can load vector and raster data from these services into QGIS. Set up a new cloud :guilabel:`Cloud` connection in the :guilabel:`Browser` panel by right-clicking on the :guilabel:`Cloud` entry and selecting :guilabel:`New Connection`. You will see a drop-down list of available cloud services. Select the service you want to connect to and fill in the required fields:

img/cloud_connection.png

Cloud Connection Dialog

You can also choose to :guilabel:`Save Connection` to an XML file or :guilabel:`Load Connection` from an XML file.