Database

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Database
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What is a Database

• A database is an organized collection of
• related information.
• An electronic database is an efficient means
• of storing and retrieving data and
• printing reports from the stored data.

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Database Terms

• A file is a collection of related records
• An entry is data that is in a field
• A field is one category of information
• A field name is the title that is assigned to a
  field
• A record is a group of related fields of one item
  of information in the database. It make up one
  row of data
• The Primary Key or Key field is the unique
  identifier for the database
• The Primary Sort is the first field used to sort
  a database (like a last name)
• The Secondary Sort is the second field used to
  sort a database

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• indicates that the data in a field is too long
• Sort is arranging records in either ascending or
  descending order
• Search, querying, or filtering is to find certain
  criteria based on given data
• Connectors are the words and, or, and not used in
  a search, query, or filter
• Comparison operators are (lt, gt, lt, gt, , ltgt)
• Example To find all the people with last names
  of Smith in Morehead City, your query/filter
  would be
• Last name Smith
• City Morehead City

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• Design View is the view of the database that
  allows the setting up of the fields and entering
  the data
• List View shows the records in a database and the
  fields similar to a table
• Report View shows the records displayed after
  search or filtering a database

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Commonly used databases

• A file is the collection of related records.
• Address books
• Dictionaries
• Encyclopedias
• Library card catalogs
• Patient data
• Student data
• Telephone directories

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Advantages of an electronic database

• Used to organize large amounts of data
• Accurate, quick and efficient arrangement of data
  in alphabetical or numerical order
• Ability to find and retrieve data
• Ability to generate reports on the database
• Ease of editing existing data

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Disadvantages of an electronic database

• Takes good planning before beginning the database
• Difficult to read text

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Steps to design a database

• Plan and design the database according to needs
  and requirements
• Determine the fields or categories that will be
  used in the database
• Determine field properties to include size and
  type

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Techniques/Devices to input data

• Keyboard
• Mouse
• PDAs
• Scanners
• Speech Recognition Software
• Web forms

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Example of an entry
Entry
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Examples of fields
Fields
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Examples of records
Records
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Example of database file
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Typical views of a database

• List view
• Displays several records on the screen at a time
• Form view
• Displays one record on the screen at a time.
• Commonly used in data entry.

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General data types

• Currency ()
• Date (03/03/03)
• Numeric (450)
• These numbers can be used in calculations
• I.E. Gross pay, basketball statistics, etc.
• Text/General (Smith)
• Numbers may used, but would not be computed
• I.E. Social security numbers, telephone numbers,
  etc.

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Sortingto arrange data in alphabetical or
numerical order

• Ascending order (1-10 or A-Z)
• 1,2,3,4,5
• Adams, Petteway, Rodriquez
• Descending order (10-1 or Z-A)
• 5,4,3,2,1
• Rodriquez, Petteway, Adams

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Primary/Secondary Sorts

• Primary key The field selected as the unique
  identifier for the database.(i.e. Student
  number)
• Primary sort The first field that a database is
  sorted on.
• Secondary sort The second field that a database
  is sorted on.

Primary Key Student No.
Secondary Sort Age (in ascending order)
Primary Sort Last name (in Descending order)
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Searching/Querying/Filteringto find specific
data based upon a given criteria or condition

• Queries/Filters use connectors and comparison
  operators to define the search criteria
• Connectors (AND, OR, NOT)
• Comparison operators (lt, gt, lt, gt, , ltgt)