reading-notes

Database Normalization

• process used to organize a database into tables and columns
• table should be about specific topic
• spreadsheet
• limiting a table reduces number of duplicate data
• eliminates some issues of modification
• reasons for normalization
  • minimize duplicate data
  • minimize or avoid modification issues
  • simplify queries

3 normal forms

• 1nf, 2nf, 3nf
• less prone to modification issues
• First Normal Form
  • info stored in table with each column containing atomic values, no repeating groups of columns
• Second Normal Form
  • In first form and all columns depend on primary key
• Third Normal Form
  • in second form and all columns not transitively dependent on primary key

Data Duplication and Modification

• increases storage
• decrease performance
• difficult to maintain changes

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