CSC 4402 20090831

CSC 4402 20090831 - Relational data manipulation is...

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CSC 4402 8/31/2009 Page 1 of 1 Data models A data model is a collection of tools for describing: Data Data relationships Data semantics Data constraints The 3 major components of any data model are: Data structures Data manipulation Data integrity An object-oriented/object-relational database starts with a relational database, but is expanded to support operations that maintain the relationship between objects and data. Relational data model The relational data model is based on a data structure of tables.
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Unformatted text preview: Relational data manipulation is performed by relational algebra or relational calculus. There are two integrity rules: 1. Entity integrity you cannot have invalid values in an entity 2. Referential integrity When referencing values from one table to another, the referenced value is guaranteed to exist. Database languages Structured Query Language (SQL) is a declarative DML. SQL contains a DDL and DML. Database design...
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This note was uploaded on 01/25/2010 for the course CSC 4402 taught by Professor Staff during the Fall '08 term at LSU.

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