Explain Why and How an Unnormalized Relation Should Be Converted

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Examlex · Accepted Answer

The Answer is A table in a particular normal form possesses a certain desirable collection of properties. Although there are several normal forms, the most common are first normal form, second normal form, and third normal form. According to the definition of a relation, a relation (table) cannot contain a repeating group in which multiple entries exist on a single row. However, in the database design process, you might create a table that has all the other properties of a relation but contains a repeating group. Removing repeating groups is the starting point when converting an unnormalized collection of data into a table that is in first normal form. A table (relation) is in first normal form (1NF) when it does not contain a repeating group. To convert a table with repeating group(s) to first normal form, you remove the repeating group(s). When you convert an unnormalized table to a table in first normal form, the primary key of the table in first normal form is usually the primary key of the unnormalized table concatenated with the key for the repeating group. The key for the repeating group is the column in the repeating group that distinguishes one occurrence of the repeating group from another.

Explain Why and How an Unnormalized Relation Should Be Converted

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