Write to Search Index has one output port, called Error Port, which collects data for records that could not be processed and added to the search index. Records that pass through the error port into the sink are considered malformed.

Records are forwarded to the error port if the value of the KeyField in the input record is blank or null. For the search index engines that support standalone searches (the legacy index engine), the error port functions only for the Update and Delete operations. However, for distributed support index engine, it collects malformed records for all the four operations: Create, Update, Delete, and Append.