FULL OUTER JOIN

The FULL OUTER JOIN command combines matching rows with all rows from both the left- and right-side tables.

SELECT column(s)
FROM table_A
FULL OUTER JOIN table_B
  ON table_A.column(s) = table_B.column(s)
WHERE condition;

One or more matching column(s) can be selected and joined from table_A and table_B based on matching columns between tables in the ON clause to define which rows are combined. Other rows from each table appear in the result separately. The results can be further filtered based on a condition in the WHERE clause.

The following example selects all the rows (*) from the books table with an author_id less than 11, and any rows from the authors table that have a matching id in the filtered books table:

SELECT *
FROM books
FULL OUTER JOIN authors
  ON books.author_id = authors.id
WHERE author_id < 11;