About the AVEVA Historian OLE DB provider

OLE DB (short for "Object Linking and Embedding for Databases") is an application programming interface (API) that allows COM-based client applications to access data that is not physically stored in the SQL Server to which they are connecting.

OLE DB provides access to different types of data in a broader manner. By using OLE DB, you can simultaneously access data from a variety of sources. A query that accesses data from multiple, dissimilar data sources such as these is called a "heterogeneous" or "distributed" query.

SQL Server uses OLE DB to make linking data between the data sources easier. Through OLE DB, Microsoft SQL Server supports Transact-SQL queries against data stored in one or more SQL Server and heterogeneous databases without any need for specialized gateway server applications.

The interface required to access data in a non-local data store (such as the AVEVA Historian history blocks) is provided by a "virtual" server, called an OLE DB provider. OLE DB providers allow you to use the power of the SQL Server query processor to make linking data stored in the SQL Server databases and from history blocks much easier and more robust. Also, the AVEVA Historian OLE DB provider has a rich set of query capabilities.

The name of the AVEVA Historian OLE DB provider is "INSQL". The AVEVA Historian OLE DB provider is installed during AVEVA Historian installation and then associated, or linked, with the Microsoft SQL Server. For information on the syntax for linking the AVEVA Historian OLE DB provider, see Linking the AVEVA historian OLE DB provider to the microsoft SQL server.

Note: The INSQL OLE DB provider cannot be used in a standalone mode.

To access AVEVA Historian historical data using OLE DB, any COM-based client application must connect directly to the SQL Server and then specify to use the AVEVA Historian OLE DB provider in the syntax of the query.

When you execute a query and specify the AVEVA Historian OLE DB provider in the syntax, the Microsoft SQL Server parser will pass the appropriate parts of the data request to the AVEVA Historian OLE DB provider. The AVEVA Historian OLE DB provider will then interface with the retrieval service to locate the data store, extract the requested information, and return the data to the Microsoft SQL Server as a rowset. Microsoft SQL Server will perform any other processing required on the data and return the data to the client application as a result set and a set of output parameters, if applicable.

The AVEVA Historian OLE DB provider must be present on the server running Microsoft SQL Server. The set of Transact-SQL operations that can be used to retrieve data in the history blocks depends on the capabilities of the AVEVA Historian OLE DB provider.

For more information on OLE DB, see your Microsoft documentation.