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Discuss the problem of Spurious tuples and how we may prevent it.
Ans: A spurious tuple is, mainly, a record in a database that gets created while two tables are joined badly. In database-ese, spurious tuples are formed while two tables are joined on attributes which are neither primary keys nor foreign keys. To prevent spurious tuples, avoid joining relations that consist of matching attributes that are not (foreign key, primary key) combinations as joining on such attributes may generate spurious tuples.
Drawbacks of Database systems ?
In a Hierarchical model of data records are organized ? In the hierarchical model of data records are organized as Tree structure.
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