Meaning of NULL in perl5 documentation

Hi,

My question is this: In the man page for the Pg perl module, the
description of the fetchrow function reads as follows:

"New style only ! Fetches the next row from the server and
returns NULL if all rows have been processed. Columns
which have NULL as value will be set to undef."

Does this mean that (in perl terms) the fetchrow function will
return an undef when there are no more rows, or the string "NULL", or
something else altogether?

Thanks,
Brendan
--
Brendan McKenna
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