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Database (Database Management System (DBMS) (the last frontier of an…

- - - - or by means of replication
        
        which can reduce the retrieval time
        
        but is a challenge to maintain updated
      - by means of fragmentation
        
        which can increase confidentiality
- - - - each row is a tuple, a collection of values
      - each column is an attribute of the data
        
        cell is the combination of row and column, an atomic value
      - design suggest to encapsulate a subject
        
        when the subject is confuse or table are overloaded with meaning make a
        lossless decomposition
    - - to connect different subjects
    - - pick rows from a table - SELECT
      - pick attributes from the tuple - PROJECT
      - unit results from two or more tables - JOIN
      - a language that abstract the basic operations in declarations - SQL