Known issues

Nodes and edges

Cognite Data Fusion (CDF) stores nodes and edges in an industrial knowledge graph, with edges pointing to industrial resource types such as time series and 3D information.

We recommend that your data models include metadata (for example, equipment, work orders, and documents) but not all data points, or machine-generated events that can number in the billions. In a multi-tenant environment, the limit is 5 million nodes and edges. Contact your sales representative to increase this quota.

Writing relational data

When writing relational data (for example, nodes or edges with references to other nodes), we allow you to automatically create references to nodes that don't yet exist. This may cause conflicts if multiple write transactions attempt to create the same nodes automatically. To resolve the issue, you must ingest data in the correct order so that all referenced nodes exist before they are referenced.

Number of transformations per type

Each data model type has a unique structure, and you need one transformation per type and one transformation per edge type.

If your data model has the types Asset and Document where one of the properties on Asset is a list of all relevant documents, you will need three transformations; one for Asset instances, one for Document instances, and one for Asset.documents edges.