SQL Right Join
1.What is returned by a RIGHT JOIN?
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A. All rows from left table
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B. All rows from right table + matched from left
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C. Only matched rows
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D. Only unmatched rows
All rows from right table + matched from left
All rows from right table + matched from left
2.Which is the correct SQL syntax for RIGHT JOIN?
SELECT * FROM A RIGHT JOIN B ON A.id = B.id;
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A. Correct syntax
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B. Invalid – use WHERE instead
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C. Invalid – use LEFT JOIN
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D. RIGHT JOIN does not exist in SQL
Correct syntax
Correct syntax
3.What will this return?
Table A Table B
id | name id | dept
1 | Raj 1 | HR
2 | Simran 2 | IT
3 | Sales
SELECT B.dept, A.name
FROM A RIGHT JOIN B ON A.id = B.id;
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A. All 2 matched only
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B. 3 rows, name is NULL for dept = Sales
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C. Only dept = HR, IT
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D. Error
3 rows, name is NULL for dept = Sales
3 rows, name is NULL for dept = Sales
4.If RIGHT JOIN returns NULLs in the left table columns, what does it mean?
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A. Error occurred
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B. Right table didn’t match
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C. Left table has no matching value
Left table has no matching value
Left table has no matching value
5.If table A has 2 rows and B has 5 rows (no matches), how many rows in A RIGHT JOIN B?
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A. 2
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B. 5
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C. 7
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D. 0
5
5