Schema changes in multi-user mode

[Zaphod]

Hello fellow peggers,

I heard thru the grape vines that version 9.1D of Progress allowed schema changes to a database opened in multi-user mode, and with users accessing it.

Apparently you can check if a particular table is in use, and if not you can put a table lock on it, make your changes, recompile the code and release the table lock. If a user tries to execute a procedure that uses that table while there is a lock on it, he would get a message like "** table locked by ... wait or press CTRL-C".

Has anyone heard about this or am I dreaming.

 

[toby.Harman]

It certainly wouldn't supprise me.

This is something that has been discussed and this mechanism fits with what I remember of the discussion.

Now that the CRC checks are at the field level and there are record versions, there is no reason why this wouldn't work.

However I don't think this gets around all the problems of deploying the new R-Code (unless there's a funky new feature there!) so you'd have to be careful that the records don't get into the new version before the R-Code is released/recompiled!

Toby