ACIS 1504 Study Guide - Midterm Guide: Data Definition Language, Referential Integrity, Unique Key

• School: Virginia Tech
• Department: Accounting and Information Systems
• Course: ACIS 1504
• Professor: Jean Lacoste

Document Summary

Required new record is entered a value must be entered or an error message will display. Database: a collection of information that you organize and access according to the logical structure of that information. Relational database: (1) information itself, stored in a series of two-dimensional tables, files, or relations, (2) the logical structure of that information. Tables, files, and relations are interchangeable for the series of two-dimensions. Primary key: a field (or group of fields in some cases) that uniquely describes each record. The file is sorted first by the primary key. Foreign key: a primary key of one file that appears in another file: within each file, you can see specific pieces of information or attributes (fields) Explain the benefits of using databases over spreadsheets or other file types: ad-hoc information retrieval, only relevant data is output, shared access, security, referential integrity can be enforced automatically, data independence, data integrity.