Database Export

A Database Export Task exports features from one of the configured databases to a ZIP file.

Step 1 (Task name)

Option Description

Task Name

Name of the task.

Create or overwrite Datasource

Select whether to create a new datasource or overwrite an existing one

Datasource Name

If an existing data source is to be overwritten, select the source here.

Click NEXT STEP to continue.

Step 2 (Database)

In this step, the source database for the export process must be selected.

Select Database

Choose the database from which the data will be exported.

The system lists the available configured databases. Select the appropriate one from the dropdown menu.

If the required database is not listed, it must first be configured in the administration section.
See Database Management for instructions on how to create and manage database connections.

Validate Connection to Database

After selecting the database, click Validate Connection to Database to verify that the connection is working properly. This validation is optional but recommended.

This step ensures:

  • The database is reachable

  • Credentials are correct

  • The export task can be executed without connection issues

Once the connection is successfully validated, click NEXT STEP to continue.

Step 3 (Task settings)

In this step, configure the output file and the export options.

Output File

Choose a name for the output archive (for example, my-export).

The export result is provided as a .zip archive for download.

If the export includes texture images, they are included in the archive under appearance. If the export includes library objects used by implicit geometries, they are included under library-objects.

Export Format

Select the output format:

  • CityGML (default)

  • CityJSON

Version

Select the version of the chosen export format.

The available versions depend on the selected database (VCDB 4 vs VCDB 5).
Option Description Default value

CityGML version

  • VCDB 4: Fixed to 2.0.

  • VCDB 5: Selectable versions are 3.0, 2.0, and 1.0.

VCDB 4: 2.0; VCDB 5: 3.0

CityJSON version

  • VCDB 4: Fixed to 1.0.

  • VCDB 5: Selectable versions are 2.0, 1.1, and 1.0.

VCDB 4: 1.0; VCDB 5: 2.0
Exporting CityGML data to a version different from the one originally imported may lead to data loss because CityGML versions are not fully compatible. Content that cannot be converted automatically is skipped. For details, refer to the VC Database documentation on compatibility and data migration.

Exporting to CityJSON

For VCDB 5 databases, CityJSON exports for version 1.1/2.0 are generated as CityJSON Text Sequence (CityJSONSeq). This supports streaming large exports by writing one CityJSONFeature object per line. CityJSON 1.0 does not support streaming/CityJSONSeq and is therefore recommended only for smaller datasets.

For large exports, consider using the Filter Options of this task to reduce the export size.

Export Options

These settings control performance and processing behavior.

Option Description Default value VCDB 4 VCDB 5 Output format

Export Appearances

If enabled, appearance information (materials, textures) is exported as well.

On

Yes

Yes

CityGML, CityJSON

Themes

Optional list of appearance themes to export (comma-separated).

If left empty, all appearances are exported. Use none to include appearances that do not have a theme.

Only relevant when Export Appearances is enabled.

Click on Get appearance themes from database (Get from database) icon to fetch available themes from the database.

(empty)

Yes

Yes

CityGML, CityJSON

Number of Threads

Number of parallel threads used during export. Each thread requires a separate database connection.

The default value in the Publisher UI is 4. Setting the number of threads too high can lead to performance issues due to thrashing. Ensure your database can handle the required number of simultaneous connections.

4

Yes

Yes

CityGML, CityJSON

Log Level

Defines the minimum severity of events that are shown in the task log. All messages of that severity or higher are included.

See Log Level below.

info

Yes

Yes

CityGML, CityJSON

LoD Filter

If enabled, export only features with matching Levels of Detail (LoD).

Use:

  • LoDs: Select one or more LoDs (for example, 2 and 3).

  • Mode: Defines how multiple LoDs are handled (default: OR):

    • OR: Export features that have at least one of the selected LoDs.

    • AND: Export only features that have all selected LoDs.

    • Minimum: Like OR, but only export the lowest LoD of the selected LoDs that is present.

    • Maximum: Like OR, but only export the highest LoD of the selected LoDs that is present.

  • Search Depth: Number of subfeature levels to search for matching LoDs. Use 0 to consider only the feature itself and its boundaries (default: 0). Higher search depths can significantly increase query time.

Off

Yes

Yes

CityGML, CityJSON

Feature Validity

If enabled, filter features by their validity in time.

Fields in the UI:

  • Validity Mode: Export Valid, Invalid, or All features.

  • at: If enabled, set Validity Date and Validity Time using the date/time picker. The task checks validity at that point in time.

  • Reference (VCDB 5 only): Select the time reference used for validity checks:

    • Database: A feature version is considered valid if it exists in the database at the selected time (based on the columns creation_date and termination_date).

    • Real World: A feature is considered valid if it is valid in the real world at the selected time (based on the columns valid_from and valid_to).

  • Lenient Validation (VCDB 5 only): Validity checks are strict unless Lenient Validation is enabled. If enabled, treat incomplete validity intervals as valid.

Off

Yes

Yes

CityGML, CityJSON

Log Level

Defines the minimum severity of events that are shown in the task log. All messages of that severity or higher are included.

The available log levels, ordered from highest to lowest severity, are:

Level Description Default value

fatal

Critical errors causing immediate termination (least output).

error

Non-recoverable errors.

warn

Warnings about potential issues.

info

General operational messages.

Default

debug

Detailed debugging information.

trace

Most detailed logs for troubleshooting.
Use debug or trace for debugging or in support cases.
Exporting historical versions requires that these versions remain in the database. Features that were physically deleted cannot be exported anymore. To preserve history, terminate features instead of deleting them (see Database Delete, Mode = Terminate).

Filter Options

These options allow restricting the export to a subset of features.

Option Description Default value

Feature IDs

Comma-separated list of feature identifiers to export.

Feature Types

One or more feature types to export.

Examples (as shown in the UI):

  • Building

  • Bridge

  • CityFurniture

  • CityObjectGroup

  • GenericCityObject

Clicking on Get feature types from database (Get from database) icon restricts selection to feature types that exist in the selected database.

Bounding Box

Spatial filter defined as x_min,y_min,x_max,y_max in EPSG:4326 coordinates (WGS84). The Publisher UI currently supports EPSG:4326 only.

Use Get bounding box from database (Get from database) icon to automatically fill the bounding box with the spatial extent of the data in the selected database.
Click on Edit bounding box (Edit bounding box) icon to open the map editor and draw or adjust the extent.

Off

Bounding Box Mode

Defines how the bounding box filter is applied:

  • Intersects: Export features whose bounding box overlaps the filter bounding box.

  • Contains: Export only features that are fully inside the filter bounding box.

  • On Tile (VCDB 5 only): Export features whose bounding box center lies within the filter bounding box (useful for tiled exports).

Intersects

Count limit

Limit the number of exported features and optionally skip a number of features at the beginning of the result set.

Use:

  • Limit: Maximum number of features to export (default: 1000).

  • Start index: 0-based index of the first feature to export (default: 0).

Off

Expert Filter

Click on (Expert filter) the icon to show the expert filter editor for entering filter expressions directly.

For VCDB 4 databases, the expert filter uses XML query expressions.

For VCDB 5 databases, the expert filter uses JSON-based filter expressions that allow advanced filtering of features.

For more information, refer to the VC Database documentation on Filtering features to delete.

Off
The limit and start index apply to the filtered result set and can be used separately or together. This enables pagination-style exports when working with large datasets.
When using multiple filters, all conditions must be satisfied for a feature to be exported.

CityGML Upgrade Options

These options are only available for exports from a VCDB 5 database.

These options help resolve compatibility issues when exporting data that originally comes from CityGML 2.0 or 1.0.

Option Description Default value

Use LoD4 as LoD3

Map LoD4 geometries to LoD3, replacing an existing LoD3.

Off

Map LoD0 Roof Edge (CityGML only)

Map LoD0 roof edge geometries onto roof surfaces.

Off

Map LoD1 MultiSurfaces (CityGML only)

Map LoD1 multi-surfaces onto generic thematic surfaces.

Off
When exporting to CityJSON, only Use LoD4 as LoD3 is supported. The other upgrade options apply only to CityGML exports.
For more information about these options, refer to the VC Database documentation on CityGML upgrade options.

Write Options

Option Description Default value

Fail fast on errors

If enabled, stop the export immediately when an error occurs.

Off

Pretty Print

Only available for exports from a VCDB 5 database and when exporting to CityGML or CityJSON 1.0.

If enabled, the exported output is formatted (whitespace/indentation), which can improve readability but may increase file size.

On

Click NEXT STEP to continue.

Step 4 (Task schedule)

Option Description

Start Job as soon as possible

Start the job immediately.

Start Job once at given time

Schedule job for a future time.

Repeat Job

Automatic periodic execution of the job.

Publish Job after Completion

Once conversion is successful, the datasource is published automatically.