How to Log OPC UA Data to SQLite

Open Automation Software can be configured to connect to OPC UA servers using the OPC UA connector and log the data to a SQLite database. This guide walks you through downloading and installing OAS, configuring an OPC UA data source connector, configuring tags and logging them to a SQLite database.

ℹ️ For simulation purposes, you will use the OPC UA server available in the OAS platform to write a Tag value. If you already have an OPC UA server or device available, you can also adjust your configuration to suit your own OPC UA server or device.

1 - Download and Install OAS

If you have not already done so, you will need to download and install the OAS platform.

Fully functional trial versions of the software are available for Windows, Windows IoT Core, Linux, Raspberry Pi and Docker on our downloads page.

On Windows, run the downloaded setup.exe file to install the Open Automation Software platform. For a default installation, Agree to the End User License Agreement and then click the Next button on each of the installation steps until it has completed.

If you'd like to customize your installation or learn more, use the following instructions:

• Windows Installation
• Linux Installation
• Raspberry Pi Installation
• Docker Installation

The OAS Service Control application will appear when the installation finishes on Windows.

Click on each START SERVICE button to start each of the three OAS services.

2 - Configure OAS

Configure OAS is the main application used to configure local and remote OAS instances.

1. From your operating system start menu, open the Configure OAS application.

2. Select the Configure > Tags screen.

   Important

   If this is the first time you have installed OAS, the AdminCreate utility will run when you select a screen in the Configure menu. This will ask you to create a username and password for the admin user. This user will have full permissions in the OAS platform.

   For further information see Getting Started - Security.

3. If this is the first time you are logging in, you will see the AdminCreate utility. Follow the prompts to set up your admin account. Otherwise, select the Log In menu button and provide the Network Node, username and password.

   

   

3 - Configure OPC UA Data Source

In the following steps you will create and configure a OPC UA Connector to connect to the OAS internal OPC UA server on port 58728 and act as a data source.

ℹ️ If you want to use your own third-party OPC UA server you can provide the relevant Server URL and security credentials instead of the details provided below.

1. Select Configure > Drivers from the top menu.

   

2. Enter a meaningful Driver Interface Name to give this driver interface instance a unique name.

3. Ensure the following parameters are configured:

   • Driver: OPC UA
   • Server Url: opc.tcp://localhost:58728

4. Click on the BROWSE button to select a Security Profile. Choose the appropriate security profile. For this guide we will choose None:None:Binary.

   

5. Enabled User Security and enter the Username and Password credentials created in the earlier section.

   

6. Click on the ADD DRIVER button on the left hand side to add this driver configuration. Once added, the driver interface name should appear in the list of drivers.

   

4 - Add Data Source Tag

In this section you will create a Tag to represent your data point in the field (for example a temperature sensor). This can then be transferred your desired destination.

1. Select Configure > Tags from the top menu.

   

2. If you want to add a Tag to the root Tags group make sure the Tags node is selected in the tag list and click on the ADD TAG button.

   

   If you want to add a Tag to a Tag Group, select the Tag Group first and then click on the ADD TAG button.

   You can also add Tag Groups by using the ADD GROUP button.

3. Provide a Tag Name such as TemperatureSensor and click the OK button.

   

5 - Assign OPC UA as Tag Data Source

You will now set the Tag's data source to the OPC UA driver interface that you created previously to act as a data source.

1. Select the Tag that will source data from the local OPC UA data source.

   

2. Set the Data Source to OPC UA.

3. Set the Select Driver Interface drop-down to the OPC UA Connector interface created previously.

4. Click on the BROWSE button next to the NodeId field. In the BROWSE OPC UA SERVER window you can select the Local node, then select OPCUA_TemperatureOutput. In the right hand VARIABLE section select - Value. You should see the Node ID is now OPCUA_TemperatureOutput.Value.

   Click on the OK button to select this Tag.

   

5. Click on the Apply Changes button to apply the changes.

   

6. Check that the quality status is Good Quality and the data in the Value field is as expected.

   

7. If you change the value of the OPCUA_TemperatureOutput Tag then you should see the same value update in the TemperatureSensor Tag. This means your OPC UA interface is working.

6 - Configure Data Logging

You will now configure data logging to a local SQLite database file.

1. Select Configure > Data Logging from the top menu.

   

2. Enter a meaningful Logging Group Name to give this data logging group a unique name. A data logging group is simply a data logging configuration for a set of Tags.

3. On the Common tab leave all the default values. This will create a configuration that uses Continuous logging with a 1 second Logging Rate. This simply means, log data at a rate of 1 second.

   

4. On the Tags tab you will add all of the Tags that you want to log. Each Tag will be a field (column) in the database. Click on the ADD button to bring up the Tag Browser.

5. Select the Tag you want to add in the left hand panel and then ensure the Value property is selected and then click on the OK button.

   

   Tips

   Each Tag has dozens of properties that are available for you to access. The Value property is the most commonly used property as it presents the Tag's current value. This is what we want to log to the database.

6. The Database Tag window will appear. This is where you set the database field name (column name) and the database data type that will be used. The most common types will be Double Float, Boolean, Integer and String.

   Let's set the field name to Temperature. Now click on the OK button.

   

7. The Tag will appear in the list of Tags to be logged.

   

8. On the Database tab you will configure the database type and connection parameters:

   • Tick the Log to Database checkbox to enable logging to a database
   • Set the Provider to SQLite
   • Set the absolute File Path of the SQLite database file. This will be created automatically
   • Set Table to a table name such as Temperatures

   

9. Click on the ADD GROUP button to add the data logging group. Once added, the data logging group name should appear in the list of logging groups.

   

10. Your database logging group is now active.

7 - Verify the Database Table

You can verify your data logging configuration using a tool that can read SQLite databases such as DB Browser for SQLite.

1. Open the SQLite database file using DB Browser for SQLite.

2. Review the Database Structure tab to see the list of tables and schema of each table. You should see the table that you configured in previous steps and a DateAndTime field and one field for each of the Tags you added.

   

3. Review the Browse Data tab to see the Tag data history. You should see data logged at the the rate of the Logging Rate that you configured.

   

8 - Save Changes

Once you have successfully configured your OAS instances, make sure you save your configuration.

On each configuration page, click on the Save button.

If this is the first time you are saving the configuration, or if you are changing the name of the configuration file, OAS will ask you if you want to change the default configuration file.

If you select Yes then OAS will make this configuration file the default and if the OAS service is restarted then this file will be loaded on start-up.

If you select No then OAS will still save your configuration file, but it will not be the default file that is loaded on start-up.