I am trying to insert a record with one field as NULL but is return an ERROR:Column 'paid' cannot be null
NOTE: In Database table column paid is of type integer.
CODE
$sql="INSERT INTO `fees_receipt_temp_table`(`id`, `voucher_no`, `std_id`, `full_name`, `payable_fee`,paid) VALUES ('','$voucher_no','$std_id','$name','$payable',NULL)";