I have a scenario where I need to insert and default the values to '0' instead of NULL for numeric columns in DB using BIX extraction rule

In DB numeric column is defaulted to  0. But when I run the BIX extract rule, these default column value is replacing 0 and inserting 'NULL'. But requirement is to keep '0' instead of null.

Any suggestions on how to achieve this?

Note: making DB column ad not null is not a feasible option because it fails the insert a record into table.