> ## Documentation Index > Fetch the complete documentation index at: https://docs.cognite.com/llms.txt > Use this file to discover all available pages before exploring further. # Physical data model reference > Reference for the physical data model sheets and fields in NEAT Excel templates. This document is a reference for the physical data model sheets and fields in the NEAT Excel template: * **Metadata**: Contains information about the data model. * **Properties**: Contains the properties of the data model. * **Views**: Contains the views of the data model. * **Containers** (optional): Contains the definition containers that are the physical storage of the data model. * **Enum** (optional): Contains the definition of enum values. * **Nodes** (optional): Contains the definition of the node types. ## Metadata sheet Contains information about the data model. | Field | Description | Mandatory | | ----------- | ----------------------------------------------------- | --------- | | space | The space where the data model is defined | Yes | | externalId | External identifier for the data model | Yes | | version | Version of the data model | Yes | | name | Human readable name of the data model | No | | description | Short description of the data model | No | | creator | List of creators (comma separated) for the data model | No | ## Properties sheet Contains the properties of the data model. | Column name | Description | Mandatory | | ------------------------------ | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | --------- | | View | The view identifier to which the property belongs | Yes | | View Property | The property identifier | Yes | | Name | Human readable name of the property | No | | Description | Short description of the property | No | | Connection | Only applies to connection between views. It specifies how the connection should be implemented in CDF. | No | | Value Type | Value type that the property can hold. It takes either a subset of CDF primitive types or a View ID. | Yes | | Min Count | Minimum number of values that the property can hold. If no value is provided, the default value is `0`, which means that the property is optional. | No | | Max Count | Maximum number of values that the property can hold. If no value is provided, the default value is `inf`, which means that the property can hold any number of values (listable). | No | | Immutable | Indicates whether the property can only be set once. Only applies to primitive type. | No | | Auto Increment | Used to indicate whether the property value is auto incremented. Only applies to primitive type. | No | | Default | Specifies default value for the property. | No | | Container | Specifies container where the property is stored. Only applies to primitive type. | No | | Container Property | Specifies property in the container where the property is stored. Only applies to primitive type. | No | | Container Property Name | Human readable name of the container property. | No | | Container Property Description | Human readable description of the container property. | No | | Index | The names of the indexes (comma separated) that should be created for the property. | No | | Constraint | List of constraints (comma separated) for the data model | No | ## Views sheet Contains the views of the data model. | Column name | Description | Mandatory | | ----------- | ---------------------------------------------------------------------------------- | --------- | | View | View id, strongly advised to PascalCase usage. | Yes | | Name | Human readable name of the view being defined | No | | Description | Short description of the view being defined | No | | Implements | List of parent view ids (comma separated) which the view being defined implements. | No | | Filter | Explicitly define the filter for the view. | No | ## Containers sheet Contains the definition containers that are the physical storage of the data model. | Column name | Description | Mandatory | | ----------- | ---------------------------------------------------------------- | --------- | | Container | Container id, strongly advised to PascalCase usage. | Yes | | Name | Human readable name of the container being defined. | No | | Description | Short description of the container being defined. | No | | Constraint | List of required (comma separated) constraints for the container | No | | Used For | Whether the container is used for nodes, edges, or all. | Yes | ## Enum sheet Contains the definition of enum values. | Column name | Description | Mandatory | | ----------- | ----------------------------------- | --------- | | Collection | The collection this enum belongs to | Yes | | Value | The value of the enum | Yes | | Name | Human readable name of the enum | No | | Description | Short description of the enum | No | ## Nodes sheet Contains the definition of the node types. | Column name | Description | Mandatory | | ----------- | ----------------------------------------------- | --------- | | Node | The type definition of the node | Yes | | Usage | What the usage of the node is in the data model | Yes | | Name | Human readable name of the node being defined | No | | Description | Short description of the node being defined | No |