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Database querying using SQL
Published in Benjamin S. Baumer, Daniel T. Kaplan, Nicholas J. Horton, Modern Data Science with R, 2021
Benjamin S. Baumer, Daniel T. Kaplan, Nicholas J. Horton
When designing a database, how do you know whether to create a separate table for pieces of information? The short answer is that if you are designing a persistent, scalable database for speed and efficiency, then every entity should have its own table. In practice, very often it is not worth the time and effort to set this up if we are simply doing some quick analysis. But for permanent systems—like a database backend to a website—proper curation is necessary. The notions of normal forms, and specifically third normal form (3NF), provide guidance for how to properly design a database. A full discussion of this is beyond the scope of this book, but the basic idea is to “keep like with like.”
Database querying using SQL
Published in Benjamin S. Baumer, Daniel T. Kaplan, Nicholas J. Horton, Texts in Statistical Science, 2017
Benjamin S. Baumer, Daniel T. Kaplan, Nicholas J. Horton
When designing a database, how do you know whether to create a separate table for pieces of information? The short answer is that if you are designing a persistent, scalable database for speed and efficiency, then every entity should have its own table. In practice, very often it is not worth the time and effort to set this up if we are simply doing some quick analysis. But for permanent systems—like a database backend to a website—proper curation is necessary. The notions of normal forms, and specifically third normal form (3NF), provide guidance for how to properly design a database. A full discussion of this is beyond the scope of this book, but the basic idea is to “keep like with like.”
Development of a worldwide ferry safety database utilizing relational database approach
Published in Journal of Transportation Safety & Security, 2019
Siyu Xu, Hao Hu, Roberta Weisbrod
Notably, the completed relation schema is supposed to be checked against some rules of relational databases, including normalization and integrity constraints, to make sure all the tables are structurally correct. To achieve a balance between minimal data redundancy and maximum accessing efficiency, each table conforms to the rules of third normal form, 3NF. Besides, the relational data model is examined against integrity constraints, including entity integrity, referential integrity, and user-defined integrity.