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<p><b>Новая страница</b></p><div>== Introducing database normalization==<br />
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<OL><LI>Database normalization is useful for several reasons:</LI><LI>It helps to build a structure that is logical and easy to maintain.</LI><LI>Normalized databases are the industry standard.</LI><LI>Retrieving data will be easier.</LI></OL><br />
<OL><LI>First Normal Form means that the database doesn"t contain any repeating attributes.</LI><LI>Violations of Second Normal Form occur when the table contains attributes that depend on a portion of the primary key.</LI><LI>Second Normal Form violations can exist only when you have a multi-column primary key.</LI><LI>Third Normal Form violations occur when a transitive dependency exists.</LI><LI>All attributes in entities (columns in tables) must be dependent upon the primary key or one of the candidate keys and not on other attributes.</LI></OL><br />
1. 10. Database Normalization<br />
1. 10. 1. <br />
Introducing database normalization</div>Admin