![]() A CROSS JOIN cannot be combined with an ON condition clause. Cartesian product), the joined table contains a row consisting of all columns in o1 followed by all columns in o2. Returns all joined rows, plus one row for each unmatched left side row (extended with nulls on the right), plus one row for each unmatched right side row (extended with nulls on the left).įor every possible combination of rows from o1 and o2 (i.e. The result columns referencing o1 contain null. The result of the inner join is augmented with a row for each row of o2 that has no matches in o1. The result columns referencing o2 contain null. ![]() The result of the inner join is augmented with a row for each row of o1 that has no matches in o2. For an example, see the examples section below.) If you use INNER JOIN without the ON clause (or if you use comma without a WHERE clause), the result is the same as using CROSS JOIN: a Cartesian product (every row of o1 paired with every row of o2). (Note that you can also use a comma to specify an inner join. O2 for object_ref1 and object_ref2, respectively).įor each row of o1, a row is produced for each row of o2 that matches according to the ON condition subclause. The semantics of joins are as follows (for brevity, this topic uses o1 and INNER or OUTER) to specify the type of join. Use the JOIN keyword to specify that the tables should be joined. ![]() Each object reference is a table or table-like data source. ![]()
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