Qi is a highly flexible cloud-based sequential data historian that you use to store, retrieve, and analyze data. You create and write data to streams using a simple REST (REpresentational State Transfer) API (Application Programming Interface). The streams you create are used to store simple or complex data types to suit your application needs. An assortment of methods with customizable behaviors are available to read data and easily obtain needed information.
The primary object of the Qi architecture is the tenant. Within a tenant you create one or more Namespaces, in which data types are defined and data is stored.
You use Namespaces to separate tenants into logical entities. For example, you might want to have one Namespace for production, one for development, and perhaps another to serve as a pre-production staging area where your QA group can run certification testing.
Within a Namespace, Qi defines three different objects in which to store and manage data:
- Type: A user-defined structure that denotes a single measured event or object for storage. In Qi, a type is called a QiType.
- Stream: A basic unit of storage consisting of an ordered series of objects that conform to a type definition. In Qi, a strea is called a QiStream.
- Stream Behavior: Defines how Qi interpolates or extrapolates data during event retrieval when requests occur before, after, or between existing data events.
Each Namespace stores a separate and independent list of Type, Stream, and Stream Behavior objects.
To use Qi, you should have the following:
The following email address is available to participants of the Qi Preview for both product support and feedback:
The OSIsoft team will respond to all support requests as quickly as possible during business hours (Pacific Time).
There are two types of security accounts for Qi users:
| Account Type | Description |
| Administrator | Allowed to perform all CRUD (Create, Read, Update, Delete) operations on Qitype, stream, and stream behavior objects. Also allowed to read and write data to streams |
| User | Allowed read operations on Qi objects and allowed to read data from streams. |
Code samples for Python, .NET, Node.js, and Java can be found in the Qi-Samples repository on GitHub. Obtain Qi REST API access keys from qi.osisoft.com before running the sample code.