The chief argument in favour of the network model in

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The chief argument in favour of the network model, in comparison to the hierarchicmodel, was that it allowed a more natural modeling of relationships between entities.Although the model was widely implemented and used, it failed to become dominant fortwo mainreasons. Firstly, IBM chose to stick to the hierarchical model
withsemi-
network extensions in their established products such as IMS and DL/I. Secondly, it waseventually displaced by the relational model, which offered a higher-level, moredeclarative interface. Until the early 1980s the performance benefits of the low-levelnavigational interfaces offered by hierarchical and network databases were persuasive formany large-scale applications, but as hardware became faster, the extra productivity andflexibility of the relational model led to the gradual obsolescence of the network model incorporate enterpriseusage.
3.Draw an ER diagram for Institute management system.Assume suitabledata.4.Consider the following database and solve the given queries usingrelationalalgebra.EMP ( Emp-id, Emp-name, Emp-salary,dept-no)i) Find the employees working indept-10.
ii) Find employees having salary greater than20000.
iii) Find the dept no. of employeesmith.
SELECT dept-no FROM EMP WHERE Emp-name=’smith’ How to revoke authorization from users. Give suitableexample.5.With suitable example explain DML statements inSQL.
];
]...
6.What is an entity? Give examples ofentities.

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