macro to Compare ENTIRE row in NEW_SHEET.xls

Hi All, [I have attached same files]
I want to write a macro to Compare ENTRIE row in NEW_SHEET.xls.If any records present in OLD_Sheet.xls.Our macro should update Only Comments column [P:P] value in NEW_SHEET.xls status field.
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IF (Any OLD_SHEET Record present in NEW_SHEET) then
{
Update NEW_SHEET.COMMENTS= OLD_SHEET.COMMENTS

}
Else
{
Print "NEW RECORD" in NEW_SHEET.COMMENTS
}
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Thanks
Sugadev V.