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Writer Mode Specification

The writer allows the user to specify a writer mode, which determines what database command should be issued for each feature received.

Valid writer modes are INSERT, UPDATE and DELETE.

Writer Modes

INSERT	UPDATE	DELETE
The geometry and attribute values of each received feature that match a field in the destination Feature Service layer schema are written as a new feature in the layer. Attributes on the feature that are not present on the table’s schema are ignored.	The attribute values of each received feature are used to update existing features in a Feature Service layer. Incoming features must provide a value for the attribute that corresponds to the Object ID field on the layer.	Existing features are selected for deletion using the same technique as in UPDATE mode. Incoming features must provide a value for the attribute that corresponds to the Object ID field on the layer. Non-ID fields are ignored.
Note: The Object ID field is added to the schema at the time of Feature Service creation. Object IDs are also automatically assigned by the service, and any values supplied for the field will be ignored.	Note: Attempting to update using a nonexistent Object ID value may result in an error message from ArcGIS Portal. It is possible for a layer to disallow updates to geometries. If this is the case, a warning is written to log, and the writer will only send attribute updates to ArcGIS Portal.	Note: Attempting to delete using a non-existent Object ID value may result in an error message from ArcGIS Portal.

INSERT

UPDATE

DELETE

The geometry and attribute values of each received feature that match a field in the destination Feature Service layer schema are written as a new feature in the layer.

Attributes on the feature that are not present on the table’s schema are ignored.

The attribute values of each received feature are used to update existing features in a Feature Service layer. Incoming features must provide a value for the attribute that corresponds to the Object ID field on the layer.

Existing features are selected for deletion using the same technique as in UPDATE mode. Incoming features must provide a value for the attribute that corresponds to the Object ID field on the layer. Non-ID fields are ignored.

Note: The Object ID field is added to the schema at the time of Feature Service creation. Object IDs are also automatically assigned by the service, and any values supplied for the field will be ignored.

Note: Attempting to update using a nonexistent Object ID value may result in an error message from ArcGIS Portal.

It is possible for a layer to disallow updates to geometries. If this is the case, a warning is written to log, and the writer will only send attribute updates to ArcGIS Portal.

Note: Attempting to delete using a non-existent Object ID value may result in an error message from ArcGIS Portal.

Writer Mode Selection

The writer mode may be specified at either the feature type level or at the feature level. The default mode is INSERT. The writer mode can be specified on a per-feature basis using the fme_db_operation attribute.