Which join type selects all rows from both tables even if there is no match?

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Multiple Choice

Which join type selects all rows from both tables even if there is no match?

Explanation:
The situation described is about including every row from both tables, even when there isn’t a matching row on the other side. A full outer join does exactly that: it returns all rows from both tables, and where there isn’t a match, it fills in NULLs for the missing side. This ensures you see every row from each table, regardless of whether there’s a corresponding row in the other table. Inner joins only keep rows where there’s a match in both tables, so nonmatching rows disappear. Left (or right) joins keep all rows from one side and any matching rows from the other side, but they don’t guarantee all rows from both tables appear. Cross joins (the Cartesian product) pair every row from one table with every row from the other, which is a different behavior focused on combinations rather than matching/unmatching rows. So the full outer join is the correct description for selecting all rows from both tables even if there is no match.

The situation described is about including every row from both tables, even when there isn’t a matching row on the other side. A full outer join does exactly that: it returns all rows from both tables, and where there isn’t a match, it fills in NULLs for the missing side. This ensures you see every row from each table, regardless of whether there’s a corresponding row in the other table.

Inner joins only keep rows where there’s a match in both tables, so nonmatching rows disappear. Left (or right) joins keep all rows from one side and any matching rows from the other side, but they don’t guarantee all rows from both tables appear. Cross joins (the Cartesian product) pair every row from one table with every row from the other, which is a different behavior focused on combinations rather than matching/unmatching rows. So the full outer join is the correct description for selecting all rows from both tables even if there is no match.

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