Make up to 3NF normalization of ERD below:

erd-awal

ERD from above us see some of the shortfall on:

  1. PUNYA on the relationship between the entities with the entity PROJECT PART cardinalities not yet complete, the entity has not been there cardinalities PROJECT
  2. The occurrence of the Ternary PUNYA relationship between the entities that connect with the dependent entity PROJECT, which is where it does not have any relationship, so that the base of an over ERD  can be corrected as follows:

erd-baru

ERD from above normalization can be generated as below:

mapping

Description:
The table above forms because:

  • First, if there is a relation 1-N key on the primary entity with cardinalities 1 will be a foreign key in the entity with cardinalities N
  • Second, if there is a relation such as the MN relation KERJA into the new table with the primary key of the second entity.
  • Third, if there is a relation such as the 1-1 relation PIMPIN then select cardinalities entity with the most high place and become a primary key foreign key
  • Fourth, if there is a dependent relationship of the table primary key will be derived from the parent entity

So that the table above has formed 3NF because the dependence of field-field primary key should not be absolute (full dependent). This means there must be no transitive dependency

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