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Designing the database

Structure

Excel file structure:

  • Excel file is flat as a piece of paper.

  • It is a single file of plain text.

  • It is a single table that has no relationship with other tables.

  • It is a spreadsheet tool designed for calculations with numbers, often very complex, and it does

this very well. Relational database structure:

  • You use your browser as an interface (phpMyAdmin)

  • One or more tables that have:

    • -

      columns: fields of related data

    • -

      rows: each row is a record

  • Types of data:

    • -

      unique key: a field in each record that contains data that is unique to that record. The record can use that unique key as its name, so it can come when called.

    • -

      numbers

    • -

      dates

    • -

      text

    • -

      binary objects

Table relationships:

  • One to one: this chunk of information is used by only one other chunk of information

  • One to many: this same chunk of information is used by many other chunks of information

  • Many to many: multiple chunks of this information are used in multiples by multiple other

chunks of information Design strategy:

  • Divide the information into separate tables, grouped by how the information functions

  • Normalization: no redundant info: don't have the same information in different tables

  • Low-hanging-fruit tables (easy to design): the ones that populate the drop-down lists

MySQL commands (query language)

  • Fairly simple

  • Build and restructure tables

  • Insert, update, and delete records

  • Select data to pass on

Mary Ann Howell 10/4/08

Developing a Web Application

www.hikaripub.com

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