In each normal form, there are some known requirements, and a hierarchical relationship exists
among the normal forms. Therefore, if a relation satisfi es the requirements of 2NF, then it also satis-
fi es the requirements of 1NF. A relation is said to be in 1NF, if domains of the attributes of the rela-
tion are atomic. In other words, a relation that is in 1NF should be fl at with no repeating groups.
A relation in 1NF must not ...
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