DataBase Management Systems (DBMSs)

A. Database Concepts
   1. Data versus information
   2. Key operations
      a. Define
      b. Insert
      c. Delete
      d. Update
      e. Data Validation
      f. Query
   3. Database (DB) organization (Relational)
      DB is a collection of data files
      File is a collection of records
      Record is a collection of fields
      Field is a collection of characters/bytes
      Characters/Bytes are collections of bits
   4. Key field(s) - unique identifier for record
   5. Data dictionary - table about the DB itself
   6. Query languages
      a. Query By Example (QBE)
      b. DB Query Languages (SQL)
   7. Advantages of DB
      a. Eliminate redundancy
      b. Improved integrity
      c. Share data
      d. Reduce Development time
      e. BACKUP!
      f. Concurrency control!
      g. Powerful query languages
   8. Other data models
      a. Hierarchical
         data a "tree" of information (parents connected to one or more
      b. Network
         data a "graph" of information (data connected by relationships
         with other data)
      c. Object-Oriented
         data concerns entities and relations with those entities (somewhat
         like network)
         often merged with relational (most popular model)

B. Information Systems

   1. Collections of hardware, software, data, people, procedures
   2. Implies management at different levels
   3. May include databases, decision systems, etc.