Expose SQL Server, Oracle, and MySQL data as OPC UA nodes – no scripting, no middleware to maintain, with OPC UA-grade security built in.
Every industrial site runs two parallel data worlds. On one side, relational databases hold the information IT and the business depend on – ERP (Enterprise Resource Planning) tables, MES (Manufacturing Execution System) recipes and batch parameters, asset registries, billing records. On the other, OT systems like SCADA (Supervisory Control and Data Acquisition), HMI (Human Machine Interface), and DCS (Distributed Control System) run on real-time OPC data. When those two worlds need to talk – and increasingly, they do – most teams end up writing custom SQL scripts or middleware to move data back and forth. This article explains what SQL to OPC UA means, why custom scripting is the wrong long-term answer, and how OPC UA Server for Databases solves the problem natively.
Why Bridge SQL and Oracle Databases to OPC UA?
Relational databases and OPC UA-based control systems were never designed to talk to each other directly. A SQL Server table doesn’t know what an OPC UA node is, and a SCADA system has no native concept of a database row. Bridging the two has traditionally meant one of two things:
- Custom scripts or stored procedures that poll the database on a schedule and push values to an OPC server – brittle and broken by the next schema change.
- Middleware built and maintained in-house by a developer who now owns a permanent maintenance burden, with no built-in OPC UA security model.
Neither approach was built with OPC UA’s certificate-based encryption, authentication modes, or standardized address space in mind. Neither distinguishes between real-time and historical access. And neither survives a database migration or a column rename without a developer going back into the code. This is exactly the gap OPC UA Server for Databases closes, with no code to write or maintain.
What Is OPC UA Server for Databases?
OPC UA Server for Databases is a plug-and-play OPC UA server from Integration Objects that maps tables and columns in your relational database directly to nodes in an OPC UA address space, through a graphical configuration interface – no SQL scripting and no OPC UA programming required. Once mapped, that data is available to any standards-compliant OPC UA client – a SCADA system, an HMI, a historian, exactly as if it were live process data.
It connects natively to:
- Microsoft SQL Server
- Oracle
- Microsoft Access
- MySQL
The table-to-node mapping is done through a graphical configuration interface. No SQL scripting and no OPC UA programming required.
What Makes It Different
Most OPC servers and DIY scripts stop at reading a value and mapping it to a tag. OPC UA Server for Databases goes further: alongside native bidirectional read/write, it supports configurable insert and select query methods exposed as OPC UA method calls. This lets an OPC UA client trigger a parameterized SQL insert or select on demand – not just read a value, but actively run a query against the database – all configured graphically, with no custom code. It is the capability that separates this product from generic OPC servers and from in-house middleware.
SQL to OPC UA Architecture
The architecture behind SQL to OPC UA is straightforward, and it’s worth understanding the four stages before you configure anything:
- Source database: your SQL Server, Oracle, MySQL, Access, or Wonderware Historian instance, holding the tables you want to expose.
- OPC UA Server for Databases: connects to that database via native drivers and maps the tables and columns you choose to OPC UA nodes.
- OPC UA address space: the mapped data now exists as standard, readable and writable OPC UA nodes, secured according to the policy you configure.
- OPC UA clients: any SCADA, HMI, DCS, or historian, connects as a normal OPC UA client and reads or writes that data in real time.
Key Features of OPC UA Server for Databases
Connectivity
- Simultaneous connections to multiple databases (MySQL, Microsoft SQL, Oracle, Microsoft Access) at once
- Automatic reconnection to database servers after network glitches
- Import and export of OPC tags via CSV files
Data Access
- Read and write OPC UA node data values
- Access to both real-time and historical data
- Graphically configurable insert and select query methods
Security
- UA TCP and HTTPS transport protocol support
- None, Sign, and Sign & Encrypt security modes
- Basic256SHA256 and Basic256 security policies
- Anonymous and User Name authentication modes
- Built-in certificate management
Deployment
- Runs as a Windows service
- Compatible with Windows Server 2008 through 2019, and Windows 7, 8, 10 and 11, Windows Server 2022, 2025
- OPC Unified Architecture compliant
SQL to OPC UA: Common Use Cases
Manufacturing: MES Recipes on the SCADA Screen
Push batch parameters and recipe data straight from a SQL Server MES table into the SCADA HMI, so operators see setpoints without leaving the control room, and write production counts back to the database automatically as they’re generated.
Water & Utilities: Asset and Compliance Data Alongside Live Readings
Expose billing, compliance, or asset-registry databases on SCADA dashboards so operators can cross-reference live readings against records during inspections, without switching applications.
Oil & Gas: Historian Data Across Well Sites
Surface well-test results or data stored in Oracle or SQL Server into OPC UA-based monitoring tools, giving engineers a single, standardized view across distributed well sites.
Energy & Power: Asset Records Next to ICCP Data
Feed substation asset and maintenance records from SQL into HMI screens alongside live ICCP (Inter-Control Center Communications Protocol) data, giving operators one unified view instead of two disconnected systems.
Custom Scripts vs. OPC UA Server for Databases
| Capability | Custom Scripts / Middleware | OPC UA Server for Databases |
| Setup time | Weeks of custom development | Hours, via graphical configuration |
| Ongoing maintenance | Breaks on schema changes; needs a developer | No-code mapping; updated without writing code |
| Security model | Whatever the developer implemented – if anything | Built-in: certificates, Basic256SHA256 encryption, authentication modes |
| Real-time + historical | Usually only one or the other | Both, natively |
| Bidirectional writes | Custom-coded, case by case | Native read/write, plus configurable insert/select methods |
| Standards compliance | None – proprietary script | OPC Unified Architecture |
| Vendor support | In-house only | Integration Objects support and updates |
Getting Started: From SQL Table to OPC UA Node in 4 Steps
- Install OPC UA Server for Databases and connect it to your SQL Server, Oracle, MySQL, Access, or Wonderware Historian instance.
- Map the tables and columns you want to expose to OPC UA nodes, using the graphical configuration tool. No SQL or OPC UA coding required.
- Choose your security mode (None, Sign, or Sign & Encrypt) and authentication method (Anonymous or User Name).
- Connect any OPC UA client – SCADA, HMI, historian, or SIOTH® – and start reading and writing data in real time.
Frequently Asked Questions
Can OPC UA Server for Databases write data back into SQL or Oracle, not just read it?
Yes. It supports both reading and writing OPC UA node values, and its insert and select query methods let OPC UA clients trigger parameterized database operations directly.
Which databases are supported?
Native support covers Microsoft SQL Server, Oracle, Microsoft Access, MySQL, and Wonderware Historian.
Is OPC UA Server for Databases secure enough for industrial networks?
Yes. It supports UA TCP and HTTPS transport, None, Sign, and Sign & Encrypt security modes, Basic256SHA256 and Basic256 security policies, certificate management, and Anonymous or User Name authentication.
Does it support historical data, or only live values?
Both. OPC UA Server for Databases provides access to real-time and historical data stored in the connected database.
