Directions (Q96–100): Consider the relations X(S, Si, C) and Y(S, P, D):
| X | ||
|---|---|---|
| S | Si | C |
| J | 1 | M |
| B | 2 | N |
| R | 3 | H |
| T | 4 | G |
| Y | ||
|---|---|---|
| S | P | D |
| J | S1 | CA |
| B | P1 | AB |
| R | D1 | DC |
| A | H1 | MD |
Which join is used to get all the tuples of relations X and Y, with NULL values for the corresponding missing values?
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Correct answer: D. Full outer join
Explanation
A full outer join keeps unmatched tuples from both sides, padded with NULLs.More Database Management Systems questions
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