a) Left outer join
b) Inner join
c) Natural join
d) Right outer join
Inner Join and Non-Matched Tuples
Inner join returns only the rows that have matching values in both tables. This means that any tuples that don’t have a corresponding match in the other table are excluded from the result.
Other Join Types
- Left outer join: Preserves all tuples from the left table, even if there are no matches in the right table.
- Right outer join: Preserves all tuples from the right table, even if there are no matches in the left table.
- Natural join: Similar to inner join, but only considers columns with the same name for matching.
In summary, while outer joins include unmatched tuples in the result, inner join strictly focuses on matching rows and discards any that don’t have a corresponding match.