Re: Writing/Reading PVs from/to a DB Question

["Johnson, Andrew N. via Tech-talk" <tech-talk at aps.anl.gov>]

On Mar 10, 2021, at 5:30 PM, Manoussakis, Adamandios via Tech-talk <tech-talk at aps.anl.gov> wrote:
> 
> I have a few questions about access to PVs from an outside DB and CSS
>  
> 	• Is there an option to read/write directly to a PV from a database such as rethinkdb or mariadb?

I haven’t heard of one. If there are Relational or NoSQL databases that can accept plugins it might be possible to write one that uses CA or PVA to update an IOC or PVA server when something gets written to the database.


> 	• Is there an option for an IOC to read from a DB and then write to the PVs and also write back to the DB?

Not built in. You can now write your own link support types and you’ve long been able to write your own device support, so you might be able to write code that lets an EPICS record query and/or update an RDB/NoSQL DB.


> 	• I did see an option for CSS to connect to a DB through the JDBC, I assume this can read/write from/to that DB or is there another possible way through CSS?
> 	• With CSS is it possible to read in a file JSON/XML/Flat to populate GUI elements that then write to their corresponding PVs and in reverse write out to a file?

I can’t answer CSS questions myself.

HTH,

- Andrew

-- 
Complexity comes for free, simplicity you have to work for.