This optional parameter allows you to define a custom SQL
query to check whether an address or prefix exists in the pool. The
default is:
select STATE from RADPOOL where YIADDR='%0'
%0
is replaced by the address.
If CheckPoolQuery is set to an empty
string, no pool checking is done at startup. Delay the start of pool check
with DelayedPoolCheckTime. For more information, see
Section 3.114.22. DelayedPoolCheckTime.