FactorySQL

FactorySQL is an OPC based Middleware product by Inductive Automation that bridges the gap between industrial PLCs and SQL Databases. FactorySQL is a drag and drop .NET application that runs as a Windows service. FactorySQL version 1.0 was released in 2003 and deprecated at version 4 in 2010 with the release of Ignition Inductive Automation offers the OPC-UA module for free. As of January 2013, FactorySQL is still being sold and supported.
Groups and Items.
FactorySQL configuration is done with standard "Groups". This unit of configuration can morph from a historical logger, real-time status and control synchronizer, downtime tracker, recipe manager, etc. The group configuration defines the database connection, table, timing options, triggering options, and "direction". Direction defines whether read or write operations come from or go to the OPC server from the SQL database. "Bidirectional" allows a change from either side to be written to the other. "Groups" contain "Items". "Items" are dragged from an OPC browsing tree or manually created. Each item represents a fully qualified OPC path along with a column name in the SQL database. Items also contain scaling options, OPC information, and other modes of operation.
Features.
Features listed from vendor web site.
History.
FactorySQL was initially written to be a drag and drop OPC to SQL data logger. Functionality was introduced to become a Transaction Manager and Industrial Historian.
FactorySQL introduced SQLTags support with version 4.1 in December 2007.