SDS reference

The Sequential Data Store (SDS) is a cloud-based streaming data storage that is optimized for storing sequential data, typically time-series. It can store any data that is indexed by an ordered sequence. Use SDS to store, retrieve, and analyze data.

An SdsType, also called a type, defines the shape of a single measured event or object. A type gives structure to the data. For example, if you are measuring three things, such as longitude, latitude, and speed, from a device at the same time, then you need to include those three properties in the type.

An SdsStream, also called a stream, is a collection of ordered events, where each event is an instance of the type.

You create and write data to streams using a simple REST API. You can use the streams to store simple or complex data types to suit your application needs. You can define simple or complex indexes to arrange and relate your data. An assortment of methods with customizable behaviors are available to read data and easily obtain needed information.

Edge Data Store (EDS) includes the SDS REST APIs for reading and writing data stored locally on the device. SDS in EDS uses the same underlying technology as SDS in CONNECT data services, so the REST API structure and usage are consistent across both environments.

All SDS data on an EDS device is saved within a preset default tenant. This tenant is integrated, ensures API compatibility with cloud-based SDS platforms, and cannot be changed. Inside the default tenant, EDS offers the default namespace, which is utilized for all application, adapter, and user-defined SDS types and streams.

In addition, the default tenant includes a diagnostics namespace. EDS and installed components write diagnostic and system‑health information to this namespace. These diagnostic streams can be accessed using the SDS REST APIs to monitor the health and status of the device.

SDS is an advanced storage engine optimized for sequential and time-series data. While it is well suited for storing Open Message Format (OMF) data, SDS can also store and process data that cannot be converted to OMF. When preparing data for OMF-based egress, streams must contain only a single time‑based index to ensure compatibility with OMF requirements.