B05NormRules - FILE NORMALIZATION Normal forms are...

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FILE NORMALIZATION Normal forms are theoretically based rules that help assure that databases can be maintained effectively. Placing tables into 3rd or higher normal form also gives a set of guidelines for breaking a set of attributes into a family of tables. Done intelligently, normalizing a database should produce the same model that an Entity-Relationship analysis would have. Normal forms are defined by number. Each of them specifies a set of conditions that should be met to avoid an additional set of maintenance problems. The following simple summary previews these conditions. 1ST NORMAL FORM No repeating groups Primary keys 2ND NORMAL FORM 1NF and No partial dependencies 3RD NORMAL FORM 2NF and No transitive dependendies BOYCE-CODD NORMAL FORM No determinants that are not candidate keys 4TH NORMAL FORM No multi-valued dependencies
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PROCESS OF DATA NORMALIZATION 1. ELIMINATE REPEATING GROUPS Make a separate table for each set of related attributes and give each table a primary key. 2.
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B05NormRules - FILE NORMALIZATION Normal forms are...

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