ANTI JOIN returns rows from the first table where no matches are found in the second table. It is opposite of a semi-join. Anti-join is used to make the queries run faster. It is a very powerful SQL construct Oracle offers for faster queries. Anti joins are written using the NOT EXISTS or NOT IN constructs.
To retrive rows from the first table where no matches are found in the second table, use the following syntax:
tablename1: The table name from which you want to fetch records.
col1: The column or field name that will be return.
In the above example, we are retriving matching column values of the associated tables using