Quiz on JOINs

Join is required when

• we need to join information from multiple rows of a table in a result

• we need to join information from multiple tables in a result

• we want to join result of two queries into one

• none of the above

which of the following is correct in syntax

• Select * from tblA A, tblB B on(A.colA = B.colB)

• Select * from tblA A, tblB B where A.colA = B.colB

• Select * from tblA A natural join tblB B on(A.colA = B.colB)

• Select * from tblA A join tblB B where A.colA = B.colB

What is true about Self Join

• In case of Self Join Natural Join has no meaning

• In self join one has to use oracle syntax only

• in self join one has to use SELF JOIN keywords.

• none of the above

Which one of the following is not a type of join

• Left Outer

• Right Outer

• Both Outer

• Inner

which one of the following condition is valid for left outer join

• where A.colA (+) = B.colB

• where A.colA = B.colB(+) OR A.colB= B.colA(+)

• where A.colA = B.colB(+) AND A.colB= B.colA

• where A.colA = B.colB(+) AND A.colB= B.colA(+)

Which of the following statement is False

• (+) operator can not be used with OR operator

• (+) operator can not be used with IN operator

• (+) operator can not be used with arbitrary expression

• (+) operator can not be used with AND operator

Minimum how many condition are required for joining N tables to avoid cross join

• one condition

• N conditions

• N-1 conditions

• N+1 conditions

SET operator are used to

• combine multiple result set of a single query into one

• Set or update data in a table

• combine multiple result set of multiple queries into one

• for joining multiple tables

Which one of the following is not as SET operator

• Union

• Intersection

• Subtraction

• Union All

Which one of the following is not a requirement for using SET operator

• More than one query

• Number of columns in both the query should match

• Data type of the corresponding column of both the query should match

• column names of both the query should match