ACCT 484 Lecture Notes - Lecture 10: Mysql, Social Security Number, Tuple
20 Sep 2016
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Acct 484 day 10: normalization review, relational database model: introduction. Quick review: what are the three problems associated with a database in 1nf, convert the following into 1nf o, 1st normal form database. Describe the three problems associated with a database in first normal form. Every cell can only have one value. Identify the primary key(s) for this 1nf table. Depends on the employee number, which makes it a partial dependency: second normal form (2nf) Database is in first normal form and all the attributes in each record depend entirely on the record"s primary key (i. e. no partial dependencies) Job code determines hourly rate, this is a transitive dependency. Look at ticket file what determines value in fine: third normal form (3nf) Database is in second normal form and contains no transitive dependencies (i. e. no relationships where data field a determines data field b) Relational database history: dr. e. f. codd 1970.
