1 / 43

Databases and Data Management: Structure, Relationships, and Web Access

Learn about databases, structured fields, records, relationships, and different types of databases. Explore data management software and the use of databases on the web.

brownn
Download Presentation

Databases and Data Management: Structure, Relationships, and Web Access

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. CHAPTER 10 Databases

  2. Databases and Structured Fields • A database is a collection of information • Typically stored as computer files • A structured file uses a uniform format to store data in the file Chapter 10: Databases

  3. Fields • Contain the smallest unit of meaningful information • Each field has a unique field name • Variable-length field vs. fixed-length field Chapter 10: Databases

  4. Records • Collections of data fields Records can be displayed as rows in a table or as forms. Chapter 10: Databases

  5. Records • Each kind of record is referred to as a record type Chapter 10: Databases

  6. Records • A record that contains data is referred to as a record occurrence Chapter 10: Databases

  7. Relationships and Cardinality • A flat file is a structured file that contains only one record type • A relationship is an association between data that is stored in different record types Chapter 10: Databases

  8. Relationships and Cardinality • Cardinality refers to the number of associations that can exist between two record types Chapter 10: Databases

  9. Hierarchical, Network, Relational, and Object-Oriented Databases • A hierarchical databases arranges record types in a hierarchy Chapter 10: Databases

  10. Hierarchical, Network, Relational, and Object-Oriented Databases • The network database model allows many-to-many relationships in addition to one-to-many relationship Chapter 10: Databases

  11. Hierarchical, Network, Relational, and Object-Oriented Databases • A relational database stores data in a collection of related tables Chapter 10: Databases

  12. Hierarchical, Network, Relational, and Object-Oriented Databases • An object-oriented databasestores data as objects, which can be grouped into classes and defined by attributes and methods Chapter 10: Databases

  13. Data Management Software Microsoft Word allows you to create a table of information, such as a mailing list, which you can edit, sort, search, and print. In addition, you can merge data from the table with a template letter to create form letters, mailing labels, and envelopes. CLICK TO START Chapter 10: Databases

  14. Data Management Software Chapter 10: Databases

  15. Data Management Software • It is possible to enter data as an ASCII text file • Custom data management software • Data dependence vs. data independence Chapter 10: Databases

  16. Database Management Systems Chapter 10: Databases

  17. Database Management Systems • Database client software allows any remote computer or network workstation to access data in a database Chapter 10: Databases

  18. Database Management Systems • Multiple users can interact with the same database Chapter 10: Databases

  19. Databases and the Web • The Web provides opportunities and challenges for accessing databases • Static Web publishing • Dynamic Web publishing • Server-side program Chapter 10: Databases

  20. Databases and the Web Chapter 10: Databases

  21. Databases and the Web • Forms can collect data, as well as specifications for a query • XForms Chapter 10: Databases

  22. Databases and the Web • Several tools are available to help create server-side programs Chapter 10: Databases

  23. XML Documents • Markup language allowing field tags, data, and tables to be incorporated into a Web document Chapter 10: Databases

  24. XML Documents • Used to specify a standard structure of fields and records • Data in an XML document is searchable • XML is portable, but not optimized for many common database operations • Consider storing data in a relational database, managing it with RDBMS software, and generating XML documents for exchanging data over the Web Chapter 10: Databases

  25. Defining Fields • The term database structure refers to the arrangement of fields, tables, and relationships in a database • Store last names and first names in separate fields • Use a primary key field to make each record unique • Use appropriate data types for each field Chapter 10: Databases

  26. Defining Fields Chapter 10: Databases

  27. Defining Fields • A computed field is a calculation that a DBMS performs during processing and stores temporarily • Uppercase and lowercase are not always treated the same • Case sensitive database • Use field formats to show what the data is supposed to look like when it’s entered • Use field validation rules to filter data Chapter 10: Databases

  28. Normalization • Process that helps save storage space and increase processing efficiency • Reduces data redundancy Chapter 10: Databases

  29. Organizing Records • Records can be organized in different ways, depending on use • Sorting • A table’s sort order refers to the order in which records are stored on disk • Sort key • Indexing • Similar to the index in a book Chapter 10: Databases

  30. Organizing Records When indexed by date, the index file contains a list of keys and the record number (R#) that contains more information about the album released on that date. Chapter 10: Databases

  31. Designing the Interface • Arrange fields in a logical order • Provide visual clues to the entry areas • Entry areas should appear in a consistent position relative to their labels • Provide a quick way to move through the fields in order Chapter 10: Databases

  32. Designing the Interface • Use scrolling to create multiple screens, if necessary • Provide buttons or other easy-to-use controls for navigating through records • Supply on-screen instructions Chapter 10: Databases

  33. Designing the Interface Chapter 10: Databases

  34. Designing Report Templates • Report generators are used to specify the content and format for a database report • A report template contains the outline or general specifications for a report Chapter 10: Databases

  35. Designing Report Templates • Supply only the information required • Present information in a usable format • Information should be timely • Information should be presented in a clear, unambiguous format • Present information in the format most appropriate for the audience Chapter 10: Databases

  36. Loading Data • Data can be loaded into a database by: • Using generic data entry tools • Using a customized data entry module • A conversion routine converts the data from its current format into a format that can be automatically incorporated into the new database Chapter 10: Databases

  37. SQL Basics • Intermediary between the database client software and the database itself Chapter 10: Databases

  38. SQL Basics Chapter 10: Databases

  39. Adding Records Chapter 10: Databases

  40. Searching for Information SELECT AlbumTitle, AlbumCover FROM Albums WHERE ArtistName = ‘Jefferson Airplane’ • The AND, OR, and NOT Boolean operators are used to perform complex SQL searches • The use of parentheses indicates the part of the query to perform first Chapter 10: Databases

  41. Updating Fields UPDATE Albums SET InStock = InStock – 1 WHERE AlbumTitle = ‘G.I. Blues’ • Global updates change the data in multiple records simultaneously • Works only for records with similar characteristics Chapter 10: Databases

  42. Joining Tables • Joining tables in SQL allows you to create relationships between tables Chapter 10: Databases

  43. Lab Assignment-Create 3 Database Tables • You are a DBA at Wal-Mart Superstore and you need to create three new database tables for all the items you sell in Excel • Divide the store into 3 sections. Create 1 table per worksheet for each section. Name the worksheets after each section you create. • Create all the proper and logical field columns that will be used for each section. • Fill in the first 3 records for each table with random materials found in that section. Chapter 10: Databases

More Related