If the target table already has corresponding data, it is not inserted.

In many cases, you may encounter a requirement: the target table t (A, B, C, D, E)
Requirement: when inserting data into the target table, if the data source is the same as some columns (eg: A, B, C) of a certain record in the target table, no data is inserted.
Solution: Use lookup to associate the source SRC with the target table des, use SRC as the stream, and use des as the traffic direction. The search failure option is rejected. The data stream we need is the data on the reject stream, and the matching data stream is saved to a file at will.
TIPS: If you want to match a field such as char, you need to add spaces as needed.
Example: