Find columns containing a specific value

[#1]

I need to compile a list of all columns containing a specific value eg. 999

[#2]

This should give some ideas

Names Default To Here(1);

dt = Open("$SAMPLE_DATA/Probe.jmp");

contcols = dt << Get Column Names(Continuous, String);

c = Filter Each({colname}, contcols,
	n = Loc(dt[0, colname], 9999);
	N Items(n) > 0;
);

Show(c);