| Description |
ESRI's Geodatabase XML (GeoDB_XML) format is ESRI's open mechanism for data sharing among ArcGIS users, and for information interchange between geodatabases and external systems. GeoDB_XML is used by ArcGIS to import and export all items and data in a geodatabase such as domains, rules, feature datasets, and topologies. Using GeoDB_XML, external application can receive XML data streams that include full or partial portions of geodatabase schemas shareable between ArcGIS users, complete lossless datasets, simple feature sets (such as shapefiles) and change-only or delta record sets. The delta record-sets are XML streams that can be used to pass updates and changes among geodatabases and other external data structures.
There are three types of XML documents that can be created in ArcGIS: a workspace document, a record set document, and a data changes document.
- Workspace Document -- XML Workspace documents are used to share schema information, exchange feature datasets and all of their contents, as well as any datasets with all associated data elements that have relationships to a dataset selected for export. The Workspace documents hold all of the contents of a geodatabase or any subset of the content including all of the schema information and, optionally, the data.
The XML Workspace document contains two elements: WorkspaceDefinition and WorkspaceData. The schema, relationship, and behavior information exported as part of the WorkspaceDefinition section includes all simple and custom features data, participation in networks and topologies, network connectivity and topology rules, simple and composite relationships, and any other information associated with the geodatabase datasets. Therefore, all behavior associated with the geodatabase is preserved and can be re-created when the XML document is imported. The WorkspaceData contains the data for the dataset as well as attributes describing the dataset name and type.
Using the WorkspaceDefinition and WorkspaceData elements, workspace documents contain the schema of a geodatabase and, optionally, data from its tables. The XML Workspace Document was designed to separate the the definition from the actual data so that software agents need read only the definition section of the document to discover what it contains. By making the data section optional, a workspace document can be used to transfer only schema information. In the case of tables and feature classes, the name of the data element in the definition section corresponds to the name of the table data in the data section. Other datasets, such as topologies, geometric networks, or feature datasets, appear only in the definition section and no data is exported for them.
- Record Set Document -- The geodatabase RecordSet document is used to export the rows from a single feature class or table as simple features or attribute records. Exporting to a RecordSet document is analogous to exporting to a shapefile. The rows are exported as records, and no additional geodatabase-related information is written to the output file. For example, topologies and other feature dataset information will not be exported. Relationships to features in other tables will not be exported.
- Data Changes Document -- As part of geodatabase transaction and version management, users may want to share and work with change-only record sets. The XML Data Changes document is used to share changes or updates among geodatabases and between the geodatabase and external systems. It does this by only distributing changes that can be tracked in the geodatabase using versioning. The primary information of a Data Changes document is an UpdateGram in which only changes are delivered as part of the XML document.
The XML schema for GeoDB_XML, GdbExchange.xsd can be found in the Program Files\ArcGIS\XMLSchema directory of the file system upon which ArcGIS products are implemented.
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