CSCI N207 Data Analysis with Spreadsheets
2a. What and Why Database?
Lingma Acheson
Department of Computer and Information Science
IUPUI
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What is a Database?
• In a general sense, a database is any
organized collection of data.
• Examples:
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Grocery List
Audio CD Catalog
Phone Book
Airline Ticketing
Oncourse
Amazon
eBay
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What is a Database?
• Forms of managing data:
– Manual book keeping
– Spreadsheets
– WORD documents
– Database management tool
–…
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Why Use a Database Tool?
• From a technical point of view, a database
is organized collection of data stored using
a database management tool, e.g.
Microsoft Office Access, Oracle, Microsoft
SQL Server, MySQL.
• Purpose for using a database tool
– Better keep track of things
– Obtain information quickly
– Be able to analyze large amount of data and
gain more insight
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Why Use a Database Tool?
• Some data can be stored in a spreadsheet
• E.g.
• No problem with adding or deleting students.
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Why Use a Database Tool?
• When data involves two different kinds yet
related information –
E.g. students and advisers information
stored in a spreadsheet:
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Why Use a Database Tool?
Problems occur :
– Modification problems:
Deleting Row 6 will result in the loss of one adviser.
If changing the email in row 8, must change in row 5.
If adding an adviser with no students, null values occur. 7
Why Use a Database Tool?
– Other problems:
• Duplication, e.g. 20 students with one adviser
would result in the same advisor information
repeated 20 times.
• Confusion, e.g. if several different emails were
found for one adviser, which one is correct?
• How about using two spreadsheets, one
stores information about students, and the
other stores information about advisers?
– Question: How to reflect the relationship
between students and their advisers?
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Why Use a Database Tool?
• Solution:
Using a relational database, store students
information in one table, and advisers
information in another table, and the
database system will allow you to define
relationships among the two tables.
• E.g. STUDENT table and ADVISER table
– Can add a student without touching the
ADVISER table and vise versa.
– Can link the two tables together to see the
relationship.
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Why Use a Database Tool?
STUDENT table:
ADVISER table:
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