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carry out human resource duties includes 1. Employee2. Job3. Job history.4. Training.5. Training history. Components Required to Hold Time-Variant DataThe management of data occurs when data changes by replacing the value of the old attributes with new attributes without looking at the previous value. Time-variant data is a type of data that the values change over time, and a record of changes is advisable. Suggesting that alldata within a database are prone to change over time makes them time-variant. Certain attributes
DATABASE MODELING AND NORMALIZATION5values are not time-variant such as social security number or date of birth because they cannot change whereas values from bank accounts, student GPA may evolve over time. Time-variant storage time requires variations in a data model, which is a type of change that depends on the nature of the data. The modeling of this kind of data occurs by creating a new entity in a 1: M relationship with the original body. All new entries are entitled to new values, date of change, and any attributes involve in the modeled event (Inmon, 2004).Diagram of a 1: M SolutionSteps of the Normalization Process to Ensure 3NF LevelThe process of normalization occurs when reducing redundancies of a data within a database,or when designing or redesigning a database. There are three normal forms of normalization, which is a way to measure the depth, level to which a database has been normalized.
DATABASE MODELING AND NORMALIZATION61.The First Normal Form (1NF):The 1NF is to divide the base data into logical units called tables, of which when each table is designed, a primary key is assigned to most or all tables.2.The Second Normal Form (2NF):Within the 2NF, partly dependent data on the primarykey are taken and entered into another table. The 2NF comes from the 1NF, which is a further breaking of two tables into more specific units.3.The Third Normal Form (3NF):The 3NF is a build up from the 1NF and 2NF. In this normal form, any data not belonging of or dependent of the primary key is eliminated.