Historian SDK Overview

The Historian Software Development Kit (SDK) is a COM object designed to simplify access to Historian services and data for the purposes of application development.

This object provides the following functionality to developers:
  • Browsing Available Historian Servers
  • Browsing and Configuring Tags
  • Browsing, Adding, and Modifying Data
  • Browsing, Adding, and Modifying Alarms and Events
  • Browsing and Adding Messages and Alerts
  • Controlling the Archiving Functions of the System
  • Controlling the Collection and Interface Functions of the System
  • Adherence to Historian Security Constraints
If you need to create customized programming for the Historian server, use the Historian Software Development Kit (SDK) with Visual Basic or any application that provides a VBA programming interface, such as iFIX, Microsoft Excel or Microsoft Word. After you install Client Tools, the Historian SDK is available in the System32 folder is automatically registered. To use the SDK, set up a project reference with the Historian SDK.

You can use the Historian SDK under any Win32 platform using a development language that supports Microsoft COM/DCOM. The SDK relies on the run-time version of the Historian API. You must install the Historian API prior to the installation of the SDK on any client that accesses the Historian system through the SDK. For instructions, refer to installing Client Tools.

The Historian SDK is a COM DL(ihSDK.dll) that must be instantiated prior to use. A single instance of the SDK may connect and converse with many Historian servers simultaneously. You can create multiple instances of the SDK, however, the developer must maintain this collection and respond to events from the appropriate instance.

The following table lists general information regarding SDK naming and dependencies.
SDK DLLihSDK.dll
Class Name iHistorian_SDK
Version 5.0.0.x
Dependencies ihAPI50.dll

The following diagram describes the object model employed by the Historian SDK. For more information on the individual objects, refer to the SDK Object Reference.

Working with Comments

Comments are retrieved with a data query. To retrieve comments, request all fields from the DataValue object and then perform a DataRecordset.QueryRecordset. The comments will be contained in the DataValue.Comments collection. Comments are stored to the archive using the DataRecordset.WriteRecordset method. Store comments to the DataValue object first by calling the DataValue.AddComment method.

Adding Data

Use the DataValue object to insert data by setting the value, quality, and timestamp before calling the WriteRecordset method.

Sample SDK Program

A sample program for the SDK is included in the Samples\SDK folder when you install Historian. Refer to this sample for more detailed examples than the ones that appear in this Help system.
Note: The SDK sample is designed to work on Visual Basic 6 (VB6).