ITEC 1301 Chapter Notes - Chapter 3: Data Hub, Data Model, Data Modeling
Document Summary
Combo of characters that describes aspect of business object. Computed fields: total, average, max, and min value. Record: collection of data fields file: collection of related records. Primary key: field or set of fields that ids record. Traditional approach to data management: info systems referenced specific files. Database approach to data management: multiple info systems share pool of data. Data modeling and database characteristics o o o o o. Enterprise data modeling: investigate general data and then examines more specific data. Entity-relationship (er) diagrams: graphical symbols show organization between data o. Relational model: organize data into collection of 2d tables called relations. Domain: the constraining of attributes to a range of allowable values. Linking: combine 2+ tables through common data attributes to form new table o. Simple database program whose records have no relationship to one another. Special purpose programming language to access data in relational. Store and retrieve data that doesn"t enforce atomic conditions.