Data transformations

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Last UpdatedSep 25, 2025
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Sequential Data Store (SDS (Sequential Data Store)) supports the following data transformations on read requests:

Reading with SdsStreamViews: Changing the shape of the returned data
Unit of Measure (UOM (Unit of Measure)) Conversions: Converting the unit of measure of the data

Data transformations are supported for all single stream reads, but transformations have specific endpoints. The following are the base URI (Uniform Resource Identifier)s for the transformation endpoints:

api/v1/Tenants/default/Namespaces/{namespaceId}/Streams/{streamId}/Data/Transform/First

api/v1/Tenants/default/Namespaces/{namespaceId}/Streams/{streamId}/Data/Transform/Last

api/v1/Tenants/default/Namespaces/{namespaceId}/Streams/{streamId}/Data/Transform

api/v1/Tenants/default/Namespaces/{namespaceId}/Streams/{streamId}/Data/Transform/Interpolated

api/v1/Tenants/default/Namespaces/{namespaceId}/Streams/{streamId}/Data/Transform/Summaries

api/v1/Tenants/default/Namespaces/{namespaceId}/Streams/{streamId}/Data/Transform/Sampled

Reading with SdsStreamViews

When you transform data with an SdsStreamView, the data read is converted to the target type specified in the SdsStreamView. For details on working with stream views, see Stream views.

All stream view transformations are GET HTTP (Hypertext Transfer Protocol) requests. Specify the stream view by appending the stream view identifier to requests to the transformation endpoint. For example, the following request would return the first event in the stream as the target type in the stream view specified by the streamViewId:

Definition: The GET method is used to retrieve data on a server.

GET api/v1/Tenants/default/Namespaces/{namespaceId}/Streams/{streamId}/Data/Transform/First?streamViewId={streamViewId}

All single stream data reads support stream view transformations.

When you request data with an SdsStreamView, the read characteristics defined by the target type of the SdsStreamView determine what is returned. The read characteristics are discussed in the code samples.

Unit of measure conversions

SDS (Sequential Data Store) supports assigning units of measure (UOM (Unit of Measure)) to stream data. For more information, see Units of measure. If stream data has UOM (Unit of Measure) information associated, SDS (Sequential Data Store) supports reading data with unit conversions applied. On each read data request, unit conversions are specified by a user defined collection of SdsStreamPropertyOverride objects in read requests.

The properties of the SdsStreamPropertyOverride object are described in the following table.

Property	Type	Optionality	Description
SdsTypePropertyId	String	Required	Identifier for an SdsTypeProperty with a UOM (Unit of Measure) assigned.
Uom	String	Required	Target unit of measure.
InterpolationMode	SdsInterpolationMode	N/A	Currently not supported in context of data reads.

This is supported in the REST API (REpresentational State Transfer - Application Programming Interface) through HTTP (Hypertext Transfer Protocol) POST calls with a request body containing a collection of SdsStreamPropertyOverride objects.

Definition: The POST method is used to create new resources.

All unit conversions are POST HTTP (Hypertext Transfer Protocol) requests. The unit conversion transformation URI (Uniform Resource Identifier) is as follows:

Definition: The POST method is used to create new resources.

POST api/v1/Tenants/default/Namespaces/{namespaceId}/Streams/{streamId}/Data/Transform

Request body

The Request Body contains a collection of SdsStreamPropertyOverride objects.

The example request body below requests SDS (Sequential Data Store) to convert the Measurement property of the returned data from meter to centimeter.

[

{

"SdsTypePropertyId" : "Measurement",

"Uom" : "centimeter"

}

]

All single stream data reads with streams that have specified UOM (Unit of Measure)s support UOM (Unit of Measure) conversions.

Edge Data Store