CP102 Chapter Notes -Object Query Language, Query Language, Data Cube
Document Summary
Ch11 behind the scenes: databases and information systems. Database: collection of related data that can be easily stored, sorted, organized, and queried: most practical when there"s complex data that needs to be organized or shared. Problem with lists: data redundancy and inconsistency, how to handle incomplete data, organization can be labour intensive, incorrect info can be entered. Without them, you couldn"t store and retrieve large quantities of info easily. 3 main components: fields, records, tables (or files) field: database stores each category of information here: data type (field type): when fields are created in the database, user assigns this. Many object-oriented databases use object query language (oql) which is similar to structured query language. Input form speeds manual data entry, provides a view of the data fields to be filled with appropriate labels to assist database users in populating the database. Field constraint: property that must be satisfied for an entry to be accepted into the field.
