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Ch.8 Database - Coggle Diagram
Ch.8 Database
(DBMS) Database management system
Data hierarchy
Field
Record
Table
Database
Designing database
Performing effectively , accurately , efficiently
Each field unique
Additional info. : size + data type
Data types (prevent valid data)
Rules for compre data against pre-defined value
Data validation :fire:
Key fields
Unique
:red_cross: empty , duplication
Assign an
identity no.
Input mask
Prevent invalid data
Easy data entry by controlling values
Queries
To retrieve data
Perform calculations
Written in :
SQL
Structure Query language ...etc.
SQL
Query Wizard
Design View
SQL view
Microsoft access
powerful DBMS
Database Objects
Table
Forms
Reports
Queries
Macros __ automate certain tasks
Module __ contain data management
Tables in Access
at least 1 table
Create \ edit table
Datasheet View
Display in rows + columns
-- Spreadsheet
switch between views
Design View
Display underlying structure
inspect \ modify data type
Data types
Text
Memo
No.
Currency $$
AutoNumber
Yes\No
OLE subject
hyperlink
Data sorting \ filtering
Sorting __ rearrange records in specific field
Filtering __ Extract records to specific criteria
Reports
Printing data
Display data
Present summarized info.
Database concept
Revolution
Time consuming
Information is companies most valuable assets
Switching : manual filling system --> electronic filling system
Save time + Space
Instant access
Databases
Well organised information -> stored and retrieve
Different applications
Collected data of specific topic
Forms
Manipulate + display data
Well-designed form = clear + attractive format