CS453: Databases and State in Web Applications (Part 2) Prof. Tom Horton Readings • Textbook: – Chapter 17, Transactions • On the web: – Virtual labs on MySQL – Other tutorials • Quick intro: two chapters in Just Java • On-line book: – PHP and MySQL Web Development. 3/e – http://proquest.safaribooksonline.com/0672326728 DBMS and Web Apps • Server-side applications use a database instead of flat files • What are the advantages of this? Advantages of DBs • • • • Concurrent access Transactional integrity Backup, rollback,… Efficient storage of large amounts of data Relational Database Model • • • • Leading model of how to organize a DB Tables Rows and columns Keys • Multiple tables, with rows linked together by keys (“joins”) • Tables as relationships SQL: Structured Query Language • Common query language for accessing many RDBMS – Oracle, Postgres, MySQL, Sybase, SQL Server – Slight variations between implementations • Common commands: – SELECT for retrieving data – INSERT, UPDATE – ALTER Learn More… • Virtual labs, tutorials, etc. • Suggestions from CS462 veterans? Example