Multiple Choice Questions - SQL Joins - Set 6
1. Self joins can be either an outer join or an inner join.
A) True
B) False
2. A join in which the values in the columns, that are to be joined, are compared using a comparison operator, is called an . . . . . . join.
A) left outer
B) right
C) inner
D) self
3. In case of full outer join Nulls are added to the unmatched rows on . . . . . . .
A) left side
B) right side
C) both sides
D) all of above
4. If there are reasonably large tables then which of the following join will use maximum system resources unnecessarily:
A) Right join
B) Left join
C) Inner join
D) Cross join
5. Joins are always done pairwise.
A) True
B) False
6. Which operators can benefit from batch processing:
A) hash join
B) merge join
C) scan
D) nested loop join
E) filter
7. Inner Joins are the default join type, so if you wish, you can use just the . . . . . . keyword in your Inner Join operations.
A) OUTER
B) JOIN
C) LEFT
D) RIGHT
8. In an equi-inner join, rows without matching values are not eliminated from the join result.
A) True
B) False
9. Outer joins are often employed when a secondary table has a foreign-key constraint to the primary table and permits nulls in the foreign key column.
A) True
B) False
10. It is possible to specify more than one join type in the query hint and allow SQL Server to choose the least-expensive one. A . . . . . . . hint takes precedence over a . . . . . . hint if both are specified.
A) query, join operator
B) join operator, query
Answers
1. Self joins can be either an outer join or an inner join.
A) True
B) False
2. A join in which the values in the columns, that are to be joined, are compared using a comparison operator, is called an . . . . . . join.
A) left outer
B) right
C) inner
D) self
3. In case of full outer join Nulls are added to the unmatched rows on . . . . . . .
A) left side
B) right side
C) both sides
D) all of above
4. If there are reasonably large tables then which of the following join will use maximum system resources unnecessarily:
A) Right join
B) Left join
C) Inner join
D) Cross join
5. Joins are always done pairwise.
A) True
B) False
6. Which operators can benefit from batch processing:
A) hash join
B) merge join
C) scan
D) nested loop join
E) filter
7. Inner Joins are the default join type, so if you wish, you can use just the . . . . . . keyword in your Inner Join operations.
A) OUTER
B) JOIN
C) LEFT
D) RIGHT
8. In an equi-inner join, rows without matching values are not eliminated from the join result.
A) True
B) False
9. Outer joins are often employed when a secondary table has a foreign-key constraint to the primary table and permits nulls in the foreign key column.
A) True
B) False
10. It is possible to specify more than one join type in the query hint and allow SQL Server to choose the least-expensive one. A . . . . . . . hint takes precedence over a . . . . . . hint if both are specified.
A) query, join operator
B) join operator, query
Answers