正在加载图片...
Drawbacks of using file systems to store data Data redundancy and inconsistency Multiple file formats,duplication of information in different files Difficulty in accessing data Need to write a new program to carry out each new task Data isolation Multiple files and formats Integrity problems Integrity constraints (e.g.,account balance 0)become "buried" in program code rather than being stated explicitly Hard to add new constraints or change existing ones Database System Concepts-6th Edition 1.5 @Silberschatz,Korth and SudarshanDatabase System Concepts - 6 1.5 ©Silberschatz, Korth and Sudarshan th Edition Drawbacks of using file systems to store data Data redundancy and inconsistency Multiple file formats, duplication of information in different files Difficulty in accessing data Need to write a new program to carry out each new task Data isolation Multiple files and formats Integrity problems Integrity constraints (e.g., account balance > 0) become “buried” in program code rather than being stated explicitly Hard to add new constraints or change existing ones
<<向上翻页向下翻页>>
©2008-现在 cucdc.com 高等教育资讯网 版权所有