Computer Science Revision Areas 0.0 / 5 ? ComputingDatabasesSoftwareGCSEOCR Created by: millardCreated on: 16-05-16 16:00 Security User Access Levels - Different users can only access certain files Firewalls - stops all access to/from the WAN which doesn't the WAN 1 of 6 Validation: Range check - Y < X < Z, is X greater than Y but less than Z? Check digit - checks that a range of numbers have been entered in the correct order 2 of 6 Types Flat File Database: All of the data is stored in one table, however data redundancy may have occured Relational Database: The data is spread over many tables, which means that redundancy is less likely 3 of 6 Definitions: Entity - A real world object about which data is stored in the table Foreign keys - link one table to another table 4 of 6 Forms & Reports Form - An input screen allowing chosen data items to be displayed/editted Report - An output of a DB, a snapshot of the data given at a time 5 of 6 Features of DBMS Application is seperate to the database Can run queries validation is carried out on the data 6 of 6
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