AR import load data in interface table.

Hello,

we have situation after doing lease entry , schedule are getting created for that particular lease, after that it is approved and than we are exporting to ar., after that data is going to insert in interface table., here one field called TAX_EXEMPT_FLAG  is getting null by default , we need to populate this with  'Y', can anyone pls advise is it possible?

If data is getting imported with TAX_EXEMPT_FLAG is null than tax amount is calculated top of invoice amount ( 100 + 5= 105 ( 5% is tax), but if TAX_EXCEMPT_FLAG='Y' than it will calculate with 100 ( 95 + 5) inclusive.

Thank you.