Experimental Physics and
Industrial Control System

Andrew Johnson <[email protected]> · Thu, 1 Mar 2018 12:03:15 -0600

On 03/01/2018 11:45 AM, [email protected] wrote:
> If the system used in a display manager changes, becomes outdated (like
> Motif), no matter - the SQL database standards are the same.
> 
> As you say, "One can already use any language, any system, to control and
> display data..." which is true, today - though I have trouble compiling
> edm for Ubuntu 64.  With this method though, a rather intensive effort
> admittedly, a display manager would be compatible with languages of
> tomorrow too, ones not even invented yet.  As long as they are SQL
> database compatible, which they will be, or they won't take off as a
> language.

I'm not aware that there is any SQL standard for notifying interested
clients when some value stored in the database changes (triggers can
only kick off other actions inside the database AFAIK). How would a SQL
database update the 30 client programs that are looking at a PV right
now when it changes, oh, now it's 33 clients, now down to 27?

- Andrew

-- 
Arguing for surveillance because you have nothing to hide is no
different than making the claim, "I don't care about freedom of
speech because I have nothing to say." -- Edward Snowdon

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System