Set this to a true or false value (not C<undef>) to explicitly specify
if this column contains numeric data. This controls how set_column
decides whether to consider a column dirty after an update: if
-C<is_numeric> is true a numeric comparison C<< <=> >> will take place
+C<is_numeric> is true a numeric comparison C<< != >> will take place
instead of the usual C<eq>
If not specified the storage class will attempt to figure this out on