Database Design Overview and Terms
Database Design (Overview and Terms)
Data - information Database - a collection of information Database integrity - database organization (how well it is organized) DBMS - database management system RDBMS - relational database management Server
Entity - a thing Attributes - characteristics Rows - vertical Columns - horizontal (imagine the standing columns of buildings) Table - made up of rows and columns Atomic value - each cell should have a data of an atomic value (smallest value)
Relationships One to one relationships One to Many relationships Many to many relationships Keys - selected group of data column(s) to serve as unique identities Primary Key - Serve as the identity of the data Foreign key - A key in the data table that is not directly related to the entity, but only shows relationship with another entity (i think) Superkey - all the possible keys that Alternative key
Schema Conceptual scema Logical schema Physical schema
Normalization Null - empty value Look up table