Web feature layers (also known as feature services) are layers that are shared to support displaying, querying, and editing data on the web. As a service editor, AllSource supports a wide range of geodatabase datasets and capabilities from supported databases. The following sections include common tasks for working with feature layers from the web in AllSource.
For more information on the sharing process, see Share a web feature layer.
Web feature layer information model
In AllSource, web feature layers support the following geodatabase functionality:
- Simple geometry—points, lines, and polygons
- Relationship classes
- Attachments
- Domains
- Subtypes
- Multipatches
- Multipoints
For web feature layers on ArcGIS Enterprise that reference data from a registered data store, the following datasets are supported in addition to the datasets listed above:
- Utility networks
- Parcel fabrics
- Topology
- Annotations
- Dimensions
- 3D object feature layers
Note:
Datasets such as feature datasets and transportation networks are not currently supported.
Web feature layers that reference database data support simple points, lines, and polygon features.
View web feature layers in the Contents pane
You can add a web feature layer to a map or scene from your active portal connection, from an ArcGIS Server user connection, by opening a web map, or by specifying a URL when adding data from a path. Web feature layers can contain sublayers. You can add the entire layer or browse into the layer to add individual sublayers. When you add a web feature layer to a map, the layer is also added to the Contents pane as a group layer containing all of the sublayers. You can rearrange these sublayers in the group layer or move them out of the group layer to stand on their own. The group layer is used for organizational purposes and does not affect layer functionality. If you add individual sublayers to a map, they are represented individually in the Contents pane.
Work with feature layers from the web
Once a web feature layer is added to AllSource, it behaves in the same way as any other feature layer from a geodatabase. To get information about the layer, access the Layer Properties dialog box. Right-click the layer in the Contents pane and click Properties or double-click the layer name. On the Layer Properties dialog box, you can set definition queries and find information about extent, data source (URL), coordinate system, and other layer properties.
When using hosted web feature layers, the owner of the layer in the portal can add and delete fields and indexes for the layer. These are the only data definition language (DDL) operations currently supported for web feature layers in AllSource. Additionally if the layer has been shared with a shared update group, members of this group will also be able to add and delete fields and indexes for the layer.
The labeling, visibility range, and symbology for the layer are set automatically based on the settings from the portal or ArcGIS Server site where it resides. You can override these settings using the Appearance and Labeling tabs or the Layer Properties dialog box.
Learn more about how to set layer properties
To help ensure good performance with data from the web, AllSource maintains a local cache for display, query, and edit operations.
Caution:
It is not recommended to cache layers that are published with definition queries if you intend to edit them. This is because service-based definition queries are not available to AllSource. When using these layers, features that do not meet the definition query may still display in AllSource even though they will not be visible in other applications. These features may disappear during the session and will disappear the next time AllSource is opened.
Learn more about how caching works
Display limit notification
Certain web feature layers may have too many features for AllSource to display all at once. When this limit is reached, a warning notification appears in the upper corner of the application indicating Feature limit exceeded! Not all features are displayed. This indicates that one or more layers did not draw completely. To see all features, you must zoom in to a smaller area so that fewer features are displayed.
Spatial references
AllSource provides users the ability to specify a spatial reference of a map. When users request a map spatial reference that is different than the spatial reference of the data, AllSource will project data on the fly to the spatial reference of the map.
For web feature layers that reference a database, both the spatial reference of the underlying data and of the map used to publish will be recorded in the web feature layer's metadata. When these web feature layers are added to a map, AllSource will use the source spatial reference. This can provide a performance benefit when querying and editing, as there is no on-the-fly projection of the spatial reference.
For hosted web feature layers, data is always copied into the back end data store using the spatial reference used by the map used to share the data. If the data being shared has a different spatial reference than that of the map, AllSource will transform the data to that of the spatial reference of the map.
You can decide to use a different spatial reference by changing the map's spatial reference. For more information on how to change a map's spatial reference, see Specify a coordinate system.
Caution:
Using an older version of ArcGIS Enterprise or ArcGIS Server and a newer version of AllSource may cause some projections to be unsupported. This is due to newer projections being added to AllSource that had not been added to previous versions of ArcGIS Enterprise. In this scenario, feature layers may not draw and using a spatial reference supported by the server will be needed.
Edit web feature layers
Typically, editing web feature layers is the same as editing other vector data. The types of edits you can make to a web feature layer are controlled by the feature service properties. There are different editing patterns that are dependent on the data being published, the editor permissions, and which capabilities are enabled on the service. One such capability that affects editing patterns is the version management capability. When publishers enable this capability when they publish branch versioned data, it changes how editors can edit the web layer in AllSource
Note:
Administrators and owners of the layer can edit feature layers in AllSource even when editing is not enabled on the layer. This is true for feature layers that reference a registered data source (ArcGIS Server feature layers) and hosted feature layers.
Layer owners and administrators can also edit hosted feature layers in ArcGIS Enterprise and ArcGIS Online portals even if editing is not enabled on the layer. If the web feature layer has been shared with a shared update group, members of the group also have elevated privileges that allow them to edit the layer even if editing is not enabled on the layer.
Use ArcPy to work with data
You can use ArcPy to access web feature layers. You can open individual layers and tables by providing the URL to the feature service sublayer referenced by the layer.
Learn more about how to access web feature layers through ArcPy
Optimize web feature layer workflows
When working with web feature layers, you can optimize one of the following workflows to help improve performance or minimize the amount of work necessary to complete a task.
Append data
When possible, it is recommended that you use workflows that execute the append process on the backend data store, server, or database. This ensures optimal performance when appending a large volume of data to a web feature layer.
For example, for feature services that reference a geodatabase, it is recommended that you perform large data loading operations directly to the underlying database using the Append geoprocessing tool with a database connection. For hosted services on ArcGIS Enterprise, you can use Append operations available from the feature layer item page or ArcGIS REST API. For hosted services on ArcGIS Online, administrators and service owners can use the append geoprocessing tool with the ArcGIS REST API when the supportAppend property is true. Feature service append capabilities must be enabled for nonadministrative users to use the append geoprocessing tool with the ArcGIS REST API.
Truncate data
The Truncate operations allow deleting all features or attachments in a feature service layer. For hosted services on ArcGIS Online, administrators and service owners can use the truncate geoprocessing tool with the ArcGIS REST API when the supportTruncate property is true.
Calculate fields
To improve performance with field calculations, use the Calculate Field geoprocessing tool to calculate using an SQL expression when possible. The SQL option, when available, executes the calculation on the server, which improves performance.
Note:
Calculating field values on joined tables is not supported with the SQL option.
Enforce standardized SQL queries
When you write an SQL query for a web feature layer in AllSource, the queries are often validated using standardized SQL. For this reason, the ArcGIS Server site on which the feature layer is running should enforce standardized SQL if possible. This can be important when performing certain time-based SQL queries, as many supported database implementations use slightly different SQL syntax for working with time.
Only an administrator can change the standardized SQL setting for an ArcGIS Server site. ArcGIS Online uses standardized SQL queries only.
Query only feature layers from map image layers
If you have published map image layers (map services) but want to enable feature access to the data for analysis or query, you can add individual sublayers from the map image layer to your AllSource map. You can add these layers the same way you add a sublayer from a web feature layer (feature service); however, when you add map image layer sublayers, the data is not editable. This allows read-only feature access to the data without the need to publish a noneditable feature service.
Note:
To add individual sublayers, double-click to expand and browse the map image layer.
Work with date fields
For a layer to be considered time enabled for use in AllSource (for example, the time slider is available), time properties for your temporal layer must be time enabled on the feature service layer during or after publishing.
Coordinated universal time (UTC) is nearly equivalent with the current time at Earth's prime meridian (zero degrees longitude), located near Greenwich, England, and is a more precise successor of Greenwich Mean Time (GMT).
When you publish hosted feature layers, you can specify whether the date fields contain local time zone information when you publish the layer. This enables the publishing process to transform the local time data into UTC for storage in the database. If you do not specify a time zone during publishing, date values are not converted and the data is assumed to be in UTC time. When working with date and time fields in feature services, dates are generally assumed to be in UTC. When publishing feature layers that reference data in an enterprise geodatabase, if any date fields are stored in local time, you can specify a time zone for the date fields. This information is used by the feature service to convert and return date information in UTC time.
You can configure feature services to have either preferred time zones or unknown time zones. For more information, see Service parameters.
When a service has a preferred time zone defined, all date values in the data will be presented in the preferred time zone. This means that for display, query, or editing, you will work in the preferred time zone only. When a service has an unknown time zone, there is no translation on the server reading the data from the data source. Therefore, AllSource will not perform any translation for display, query, or editing.
When working with web feature layers that have neither a preferred time zone nor unknown time, there are no conversions applied to date fields for query or display purposes in AllSource. Date values returned by queries in AllSource are displayed in the UTC time returned from the web feature layer. This contrasts with other applications such as web browsers that use the ArcGIS API for JavaScript. These web applications usually convert date values into the local time used on the device used to view the data. With feature layers published by reference date queries, calculations or edits may return unexpected values if the time zone of the data is not taken into account.