Embed
Email

Database

Document Sample
Database
Shared by: maria abbasi
Categories
Tags
Stats
views:
15
posted:
12/10/2011
language:
pages:
44
Overview

 What a database is

 How it fits into the broader information

management picture

 What the different parts of a database are

 How to think about information in a database-

shaped way

 The priorities involved in the database

planning process

What is a database?



A database is a storage space

for content / information

(data)

But what is data? And

where is it now?

Data is factual information about objects and

concepts, such as:

• measurements

• statistics

You can find it in:

 filing cabinets

 spreadsheets

 folders

 ledgers

 lists

 colleagues’ memories

What does “managing

information” mean?

 Making information work for us



 Making information useful



 Avoiding "accidental disorganisation”



 Making information easily accessible and

integrated with the rest of our work

Managing as re-organising

We often need to access and re-sort data for

various uses. These may include:

 Creating mailing lists

 Writing management reports

 Generating lists of selected news stories

 Identifying various client needs



Can you add to the list?

Managing as re-processing

The processing power of a database allows it

to:

 Sort

 Match

 Link

 Aggregate

 Skip fields

 Calculate

 Arrange

Databases everywhere!

Because of the versatility of databases, we

find them powering all sorts of projects:

 A web site that is capturing registered users

 A client tracking application for social service

organisations

 A medical record system for a health care facility

 Your personal address book in your e-mail client

 A collection of word processed documents

 A system that issues airline reservations

Exercise 1: Understanding data and

data-gathering

Different parts of a database

 Fields

 Records

 Queries

 Reports

Fields

 Database storage units

 Generic elements of content

Exercise 2: Breaking down

content into fields

Use the table below to break each content type into

fields. Refer to the list of example fields for

suggestions

Records

A simple table showing fields (columns) and records(rows):









And as part of an MS Access database table:

Queries

 Queries are the information retrieval

requests you make to the database

 Your queries are all about the

information you are trying to gather

Reports

 If the query is a question...

...then the report is its answer

 Reports can be tailored to the needs of

the data-user, making the information

they extract much more useful

The database planning process

What kind of database are you working

on?

 Information and referral database



 Contact/client database



 Donation database (donorbase)



 Other

Information and referral databases

 Store information about service providers

 Track and match requests for referral

 Use a simple design

 Need to be maintained with up-to-date and

complete information

Contact/client databases

 Store contact information for client base

 Sortable by criteria like:

 Client interests

 Services provided

 Subscription expiry dates

 Last contacted date

Donation databases (donorbases)

 Generate reports of donations

 Order or sort donors according to different

conditions

 Record the various donation details of each donor

 Create and sort lists of potential and current donors

 Print letters, labels and reports

Exercise 3: Database planning

 Work through the questions on the worksheet

 Be aware of the sequence (order) in which

questions arise

 Repeat the exercise with your colleagues in

your organisation

Conclusion: Database - the information

tool

 A powerful tool for managing

information

 Information first - database second

 Take your co-workers with you

 Include them at all stages of the project

planning process

 Train them properly in the use of the tool

 Develop their understanding of the capacity of

the tool

What is Microsoft Access?

Microsoft Access is a relational database management

system (DBMS or RDBMS). At the very core, it is a

software “engine” that provides an interface between

physical data and user application queries.



Other examples of DBMS applications include:



•Oracle

•mySQL

•SQL Server (Microsoft)

•DB2 (IBM)

•Informix

Definitions

 MS Access - software used for creating databases

 Quickly

 Accurately

 Using wizards and templates developed to maintain the

integrity of your data

 Data are just information

 Database

 Collection of data

 Related to a particular topic or project

Data Integrity

 Data must be accurate.

 Data are RELATED to other data in your

database (e.g., library patron is related to the

book(s) that s/he has checked out).

 Maintaining the INTEGRITY of the

relationship between different pieces of data

is very important.

 Example of compromised integrity: sending an

overdue notice to the wrong library patron

MS Access vs. MS Excel

 MS Excel

 spreadsheet

 flat database

 all information has a one-to-one relationship

 MS Access

 like multiple spreadsheets that are connected to one

another

 one-to-many relationships

 many-to-many relationships

Examples

 Printed Phone Directory (White Pages)

 Flat database: One-to-one relationships

 Library Catalog

 Relational database: Many-to-many relationships

 Library patrons check out many books.

 Books are checked out by many patrons.

 University Class Schedule

 Students have many professors.

 Professors have many students.

 Classes can be held in many classrooms.

MS Access vs. MS Excel

 The choice is simple:

 IF you have only one-to-one relationships,

you need to use MS Excel.

 IF you have one-to-many or many-to-many

relationships, you need to use MS Access.

What is in an MS-Access file

Unless advanced

techniques are employed,

all entities are stored in

one *.mdb file. When

running, a locking file

(*.ldb) is also visible.

Only the mdb file needs

to be copied to transfer

the database to another

computer or location.



Ex.

MSCI_ByrneGuestLecture.mdb

Query Overview - 1

 An MS-Access query is a set of stored SQL

instructions that manipulate and/or select data

from one or more tables.



 Select Query – Data grouping and/or filtering

 Make-Table Query – Select + creates/populates

new table.

 Update Query – Updates fields from specified

table data

 Append Query – Runs query on one table,

appends results to a table

 Delete Query – Delete selected records from table

PA Harris, Vanderbilt University

Query Overview - 2

 SQL (Structured Query Language) is a very

widely used database language designed

specifically for communicating with databases

 SQL is not proprietary – almost every DBMS

supports SQL (including MS-Access).

 SQL is relatively easy to learn, but extremely

powerful – one of the easiest ways to learn is to

use MS-Access Query by Example methods, then

look at the generated SQL command

 Remember that a query is nothing more than the

database engine running the stored SQL command

(it looks and sometimes acts like a table, but really

adds little mass to the database file)

One Table Query Example - Live

Use this

button to

toggle

between Right-Click + Add to add

design, sheet table(s)

and SQL

views.







Custom sort

by one or

more fields.

Drag and Drop Fields

2-Table Query Example - Live

Right-Click + Add to add table(s)

Note that relationship often automatic.









Calculated Field

Drag and Drop Fields

BMI: [Weight]/([Height]/100)^2



Right-Clicking gray area

above field enables

property changes.

Query – Calculating Fields



Name the calculated field, then type a colon, then

type the equation using brackets ( [ ] ) around table

fields. If there is ambiguity in the field names

between tables, you may need to type table.[field]

format.



Ex: BMI: [Weight]/([Height]/100)^2

Query – Sorting Data









Choose Ascending or Descending in the Sort Row

This query would sort by Gender THEN by Race.

You need not “show” the data field to use as a filter.

Query – Filtering Data









This query will return all records in the database for:

Females

who are not white

whose height are greater than 150 cm

and who weigh between 60 and 70 kg

Query – Filter Operators

= equals

> greater than

>= greater than or equal

not equal to

Between between two values

Is Null field is empty

is not null field is not empty

Like Matches a pattern (Like John*)

OR Logical OR (one or other is true)

AND Logical AND (both are true)

etc.

Query – Grouping Data the 1 Button

Clicking

- Totals

Enables Grouping, Counting

and Statistical Options









Running this

Query

indicates there

are 203

Females and

Notice new “Total” row. 261 Males in

Each field (column) can be set. the database.

Query – Grouping Data -2

Totals Options Include:

Group By

Sum

Avg

Min

Max

Count

StDev

Var

Query – Export Data

Create and Save

1)

Query







Use OfficeLinks (Excel Toggle

2)

Option) to “Analyze it with Excel”









Data Automatically

3)

Exported to Excel

Microsoft Access – Module 4





Creating / Working with

Forms/Reports

Graphical User Interface (GUI)



Although it is possible to enter data directly into a

table, you can enhance data quality by forcing data

entry through forms.



Depending upon your users, you may wish to set

things up so they never even see the database

window. In other words, you can design your

application so they only touch the data through

programmed forms.

Graphical User Interface (GUI)



Continuing with the glucose database we

formulated earlier, we’ll now attempt to build a

graphical user interface to:



1) Collect Data

2) Periodically report data through pre-formatted

reports

3) Quit the program

GUI – Forms/Report Live









Out of Program

MS Access – Module 4 Summary

Use forms and reports together to build a data software

application.



Design to the lowest common denominator (Murphy will

use your program early and often)



Always look for and design carrots to win over the true

data entry personnel. If it saves them time or offers

something they couldn’t do before, they might use the

application.



Look for champions – bright, energetic individuals who

will try something new, etc.

MS Access – Resources

I cannot recommend the BEST MS-Access book.

However, I can recommend the following series of books

that I usually turn to when learning new technology:



•Visual Quickstart Series – beginner/intermediate level

•O’Reilly Series – intermediate/advanced level



There is also an excellent tutorial on the web:

http://mis.bus.sfu.ca/tutorials/MSAccess/tutorials.html


Related docs
Other docs by maria abbasi
01 -Intro
Views: 2  |  Downloads: 0
04 - Basic concepts of computer systems
Views: 2  |  Downloads: 0
Database
Views: 15  |  Downloads: 0
05 - Hard Disk
Views: 2  |  Downloads: 0
Introduction Computer Networking
Views: 6  |  Downloads: 0
Alter-Manipulation
Views: 1  |  Downloads: 0
03 - Internet
Views: 2  |  Downloads: 0
02-E-Commerce Overview
Views: 3  |  Downloads: 0
Intro-E-Com-Ch-1-Modified
Views: 2  |  Downloads: 0