Hey so I’m new to ignition and trying to wrap my head around how to design an architecture for a POC that I was doing. I have mock data coming in through SCADA and I’m writing this data into a Microsoft SQL Server. I’m then connecting this db to Ignition through the database connections.
I can only see data when I go to the query editor part and write some select queries.
I’m not able to see the tag list in ignition or see data flow when I generate data and write to db. After this I learnt that the db is more of storage for live data coming from somewhere else? Is it possible to use the database as a source for live data? I was considering polling constantly but I don’t have the tag list to work with in the first place. Am I going about this in the right way? Any help would be much appreciated!
Have a look at query tags.
These tags query the database at a rate determined by the Tag Group setting.
You will have to create these tags yourself.
Anything (almost) is possible. But - to make it short - we usually use opc tags to read values from devices, then store things we want to keep in a database. Databases also are a useful for saving configurations or parameters.
Now, if you want to use a database as a live data source, nothing’s stopping you. But it raises a question: What’s populating the database ?
Are you using any historian to store the live data?
I believe meaning through a different SCADA system.
Yup the database is getting populated with device data and I’m trying to access that database through ignition. I tried to write a few query tags and I’m polling at a specific rate. If data comes in faster than that do I lose data? (Data that I get from here needs to move downstream to another process) Also I had to manually create query tags, if I have over a hundred tags will I have to manually create that many tags? Feels like what I’m doing is not a best practice
It isn’t. Ignition can do some things like this, but normally Ignition supplies data to the database, using a predefined structure with meta-data. Having the meta-data allows Ignition to query for display with convenience functions/bindings (the tag historian).
When Ignition is not the entity storing the data, it has no knowledge of the structure to go with it (the meta-data).
You’ll have to share the details of your database schema to get more useful advice.
Thanks for the replies everyone! I got a good idea of what I’m doing and what needs to be done thanks to the discussions here