John,

Forgot to answer your second question, you can return information of all open tables in a datasession with aused(), loop through the array created and use dbgetprop() to check for buffering, although my code is not this generic I use a nested do case statement within a for...endfor loop. As an example using 3 tables:

local i, lcAlias
for i=1 to 3
do case
case i=1
lcAlias=table1
case i=2
lcAlias=table2
case i=2
lcAlias=table3
endcase

endfor

cleaner code would be:
local i,lcAlias
local array laUsed[1]
lnCount=aused(laUsed)
if lnCount>0
for i=1 to alen(laUsed,1)
lcAlias=laUsed[1]

endfor
endif