mchron@aueb.gr writes:
> The problem is that while, Im running the postgres with gdb and I set a
> breakpoint at the function
> create_plan() of createplan.c, after some step commands,the gdb says that it
> cant recongnize
> the node 121 in the PostgresMain() function.
That's not what gdb said at all; all you know is that the error happened
someplace where you didn't have control. (My bet is that control got as
far as executor startup, which you already said you hadn't fixed to
understand this new node type, so the error is exactly what I'd expect.)
Perhaps you should rebuild the backend with -g (see --enable-debug) so
that gdb can actually be somewhat helpful. It's usually a good idea to
have --enable-cassert turned on when hacking C code, too.
FWIW, I don't personally ever do debugging in a standalone backend,
unless the problem is one that keeps a normal backend from starting.
It's much more pleasant to use a regular psql session to issue SQL
commands, and attach to the connected backend with gdb in another
terminal window.
regards, tom lane