Data retrieval: Transforming data into information

AVEVA Historian can process SQL-based queries from any number of client applications, including: AVEVA Insight, AVEVA Historian Client, and ad hoc SQL query tools. It can also process queries via the OData interface and from SDK client applications.

When Historian receives a request for data, it performs the following steps:

1. Locates the requested data.

   • Historized process data is stored in history blocks.

   • Configuration data is stored in SQL Server database tables.

   • Replication data is stored in history blocks.

2. Apply a retrieval mode to the data.

   Because of the enormous amount of data potentially associated with a facility, Historian provides several retrieval modes that help interpret that data, turning the collected data into usable information.

3. Returns the results to the client application.