We have some stream-of-consciousness notes from the 4Dv6 Stored Procedure class:

• Stored procedures in 4D are not the same as in other SQL-based systems. The stored procedures are actually full-blown processes, which execute asynchronously. SQL stored procedures execute synchronously.
• All of the 4D language is supported on the server, except for those commands that present a window on the screen. Externals are supported, and external windows are supported at this time, but will go away in the final build.
• The design philosophy of the new server is this: the client initiates communications with the server, but the server doesn't initiate communication with the client.
• Domi intimated that there would be a new 4Dv7 at this time next year.
• SET PROCESS VARIABLE and GET PROCESS VARIABLE, which works just fine with BLOBs, are the mechanism by which a very robust interprocess communication method may be implemented.
• Domi noted that the SET/GET PROCESS VARIABLE is much more robust than Outside call in that Outside call depends on the execution cycle. Also, S/GPV is fully asynchronous and won't "lose" messages like Outside call sometimes did.
• Q: What sort of performance penalty is there? A: It depends, of course. You have to test.
• Q: Is a SP like another user? A: No, it depends on the loading of the task; it's totally dependent on what the process is doing. Don't think of
• Q: How will tracing work on the server? A: Exactly like it does on the client! Q: You might be going back and forth between two keyboards? A: Yes! But, we have thought of an answer for that. We will be working on a memory-based network component so that it will be much more efficient to run Server and Client on the same machine. The only problem then might be to figure out to which one a trace window belongs! (Laughter)
• Q: Will SET/GET PROCESS VARIABLE work in interpreted mode? A: Yes; if the variable doen't exist it is created just like in interpreted mode.
• Q: Will CALL PROCESS work for server processes? A: Yes.
• Q: Can you send printing commands to the server? A: Yes. Now, is it a good idea... (laughter)
• Domi showed an example of a window on a Mac client controlling a thermometer on a Windows server process. Pretty cool. When he showed us the code behind the demo, the client process had only one line of code: SET PROCESS VARIABLE.
• Q: Can you get a variable from a client from the server? A: No. This would in effect halve the bandwidth of the current client-server architecture, which provides only a half-duplex channel. Making the connection go both ways would make it half as fast.

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