![]() So, the data redundancy can be avoided in this model. 9.6, none of the fields is common in any two files except the key item. The actual physical location of data does not matter to the user so long as that field appears in the data dictionary as local.Īs may be noted from Fig. The user programs do not require any change when data are first distributed or redistributed. This data independence is the core advantage of the relational model of database.Į) The distributed independence of data is another feature of a good relational database. These manipulations are possible at the record level as well as for the whole file, giving the flexibility in defining access permissions for various categories of users.ĭ) Any modification in the structure of database in terms of splitting the table horizontally or vertically should not have any impact on the logic of the program using the database. C) A data manipulation language (DML) is available to users including programmers for creation, insertion, modification, retrieval, organising and deletions of any part of the database.
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