DATABASE FUNDAMENTALS
WHAT IS DATABASE MANAGEMENT
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Outer join
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Natural join
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Self Join
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Equi join
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Detailed explanation-1: -In Natural Join, there should be at least one common attribute between two relations. It performs selection forming equality on those attributes which appear in both relations and eliminates the duplicate attributes. Example: Consider the following two tables.
Detailed explanation-2: -An equi-join is a join based on equality or matching column values.
Detailed explanation-3: -A NATURAL JOIN is a JOIN operation that creates an implicit join clause for you based on the common columns in the two tables being joined. Common columns are columns that have the same name in both tables. A NATURAL JOIN can be an INNER join, a LEFT OUTER join, or a RIGHT OUTER join.
Detailed explanation-4: -A natural join is a type of equi join which occurs implicitly by comparing all the same names columns in both tables. The join result has only one column for each pair of equally named columns.
Detailed explanation-5: -Natural Join in SQL refers to joining two or more tables based on common columns, which have the same name and data type. We do not need to specify the column used for joining two tables in natural join. Natural join is used to retrieve data from more than one table in a single place.