About the physical layer

Updated: October 31, 2025

The physical layer represents the actual data in an organization's systems. It consists of the following asset types: Database, Schema, Table, and Column.

Note

Although the Database asset type is a Technology asset, it is considered part of the physical layer.
The Schema, Table, and Column asset types are available with Data Catalog.
The Guided Stewardship operating model specifically includes asset types related to the semantic and conceptual layer, such as Data Concept, Data Domain, Data Attribute, Data Entity, and Data Model.
The Schema, Table and Column assets in Collibra are almost never created manually. They are mostly automatically created via the Data Catalog registration processes.

Schema asset type

A Schema is the highest level of physical structure in a Database. It defines, in a formal language, the structure of the tables and columns in the database. Schema assets are part of the physical layer.

Example ...

Schema assets are:

Related to...	Via the relation type...	Description
Database assets	Database has / belongs to Schema	One-to-many relation, whereby: A Database asset can have many Schema assets. A Schema asset can belong to only one Database asset.
Table assets	Schema contains / is part of Table	One-to-many relation, whereby: A Schema assert can contain many Table assets. A Table asset can be part of only one Schema asset.

Related to...

Via the relation type...

Description

Database assets

Database has / belongs to Schema

One-to-many relation, whereby:

A Database asset can have many Schema assets.
A Schema asset can belong to only one Database asset.

Table assets

Schema contains / is part of Table

One-to-many relation, whereby:

A Schema assert can contain many Table assets.
A Table asset can be part of only one Schema asset.

Table asset type

Table assets represent the physical tables in a data environment. Tables assets are part of the physical layer.

Example ...

Table assets are:

Related to...	Via the relation type...	Description
Schema assets	Table is part of / contains Schema	One-to-many relation, whereby: A Table asset can be a part of only one Schema asset. A Schema asset can contain many Table assets.
Column assets	Table contains / is part of Column	One-to-many relation, whereby: A Table asset can contain many Column assets. A Column asset can be a part of only one Table asset.

Related to...

Via the relation type...

Description

Schema assets

Table is part of / contains Schema

One-to-many relation, whereby:

A Table asset can be a part of only one Schema asset.
A Schema asset can contain many Table assets.

Column assets

Table contains / is part of Column

One-to-many relation, whereby:

A Table asset can contain many Column assets.
A Column asset can be a part of only one Table asset.

Column asset type

Column assets represent the physical columns in a data environment. It is the lowest level of definition in the physical layer.

Example ...

Column assets are:

Related to...	Via the relation type...	Description
Table assets	Column is part of / contains Table	One-to-many relation, whereby: A Column asset can be a part of only one Table asset. A Table asset can contain many Column assets.
Data Attribute assets	Data Attribute represents / represented by Column	One-to-many relation, whereby: A Data Attribute asset can represent many Column assets. A Column asset can be represented by only one Data Attribute asset.

Related to...

Via the relation type...

Description

Table assets

Column is part of / contains Table

One-to-many relation, whereby:

A Column asset can be a part of only one Table asset.
A Table asset can contain many Column assets.

Data Attribute assets

Data Attribute represents / represented by Column

One-to-many relation, whereby:

A Data Attribute asset can represent many Column assets.
A Column asset can be represented by only one Data Attribute asset.

About the physical layer

Schema asset type

Table asset type

Column asset type

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