The JOIN operations, which are among the possible TableExpressions in a FROM clause, perform joins between two tables. (You can also perform a join between two tables using an explicit equality test in a WHERE clause, such as "WHERE t1.col1 = t2.col2".)
JOIN Operation
Specifies a join between two tables with an explicit join clause. See INNER JOIN.
Specifies a join between two tables with an explicit join clause, preserving unmatched rows from the first table. See LEFT OUTER JOIN.
Specifies a join between two tables with an explicit join clause, preserving unmatched rows from the second table. See RIGHT OUTER JOIN.
In all cases, you can specify additional restrictions on one or both of the tables being joined in outer join clauses or in the WHERE clause.
For information on which types of joins are optimized, see Tuning Derby.