xDBML

xDBML is an open specification to describe a data model as text. It goes beyond DBML, with nested objects and arrays, conceptual relationships and AI-readiness metadata. Its syntax is described in the xDBML specification, and the topic Gen-AI created xDBML shows a complete xDBML document.

Hackolade Studio writes xDBML in two situations: when you forward-engineer your model from the menu, and automatically "behind the scenes" when the AI chat panel reads your model to answer your prompt. Both use the same export, so the same objects are supported.

Forward-engineer a model to xDBML

Open a Polyglot model, then go to Tools > Forward-Engineer > xDBML.... The xDBML... menu item currently appears only when the target of the model is Polyglot.

1. In the Objects selection dialog, choose what to export. Under the model, the dialog lists Containers, with the entities of each container, then Relationships and Views. Everything is selected by default. Entities that do not belong to a container are listed under Undefined Bucket.
2. Click Submit.
3. Choose the folder and the name of the file. The default file name is the technical name of the model, or its name when it has no technical name, with the extension .xdbml. In the browser version of Hackolade Studio, the file is downloaded instead.

The progress window confirms when the xDBML file is generated.

In the xDBML file, the data type of an attribute is its mode when it has one, such as int32 for an integer, otherwise its Polyglot data type, such as varchar.

Relationships and Views export all the relationships or all the views of the model, or none. A relationship is exported only when you export both its parent entity and its child entity. A view that belongs to a container is exported only when you select that container, or some of its entities.

xDBML cannot currently be generated with the Command-Line Interface.

Supported objects and properties

Hackolade Studio currently supports the forward-engineering of the following objects, from the menu and in the AI chat panel:

• the model name and description;
• containers, with their name, description and color;
• entities, with their name, description and header color in the main ERD;
• attributes with a scalar type, an object or an array, nested at any depth, with their name, description, data type, length, precision, scale and the Required property;
• primary keys and unique keys, single or composite;
• foreign key, foreign master and conceptual relationships, between two entities or between their top-level attributes;
• views, with their name, description, query and the Materialized property.

Relationships are exported with their name, description, cardinality at each end, roles, verbs and color, and with the constraint type of a foreign key: identifying or non-identifying.

Deactivated containers, entities, attributes and views are left out of the xDBML document. A deactivated relationship is exported with the inactive setting.

Hackolade Studio does not support the forward-engineering of the following objects yet:

• relationships to or from a nested attribute;
• the attributes of a view;
• indexes and check constraints;
• model definitions;
• supertypes and subtypes, ERD views and annotations;
• data lineage.

For the supported objects, Hackolade Studio does not support the forward-engineering of the following properties yet:

• default values, and validation settings such as pattern, minimum or maxItems;
• the delete and update actions of a relationship;
• the header color of views, and header colors set in ERD views other than the main ERD;
• custom properties.

For a complete view, refer to the table below. The first column gives the name in Hackolade Studio, the second the name in the xDBML specification:

Hackolade Studio	xDBML	Exported
Model name and description	project	✅ Yes
Container	container	✅ Yes
Entity	entity	✅ Yes
Attribute with a scalar type, an object or an array	field	✅ Yes
Primary key, single or composite	primary key	✅ Yes
Unique key, single or composite	unique key	✅ Yes
Foreign key, foreign master or conceptual relationship, between two entities or between top-level attributes	relationship	✅ Yes
Relationship to or from a nested attribute	relationship	TBA
View, with its name, description, query and Materialized property	view	✅ Yes
View attribute	view field	Not yet
Index	index	TBA
Check constraint	check	TBA
Model definition	named type	TBA
Supertype and subtypes	supertype group	TBA
ERD view	diagram view	TBA
Annotation	sticky note	TBA