Database. Informatics presentation "Databases

slide 1

slide 2

Databases are used to store and retrieve large amounts of information. Examples of databases: notebook, dictionaries, reference books, encyclopedias. Database - a structural information model DATABASE (DB) - a set of stored interconnected data organized according to certain rules Kolesova Zh. V.

slide 3

According to the nature of the stored information, databases are divided into: Factual databases contain brief information about the described objects, presented in a strictly defined format. For example, the library database stores bibliographic information about each book: year of publication, author, title, etc. Documentary databases contain documents (information) of the different type: textual, graphic, sound, multimedia (for example, various directories, dictionaries) Kolesova Zh. V.

slide 4

EXAMPLES OF DATABASES: DB of the book stock of the library; Personnel database of the institution. database of legislative acts in the field of criminal law; Database of modern rock music. factual documentary The database itself includes only information (DB - "information warehouse") Kolesova Zh.V.

slide 5

According to the method of storage, databases are divided into Centralized database - the database is stored on one computer Distributed database - different parts of one database are stored on many computers connected by a network Example: information in Internet networks, united by the web of WWW Kolesova Zh. V.

slide 6

According to the organization structure, databases are divided into RELATIONAL NON-RELATIONAL HIERARCHICAL NETWORK A relational (from the English word relation) is a database containing information organized in the form of rectangular tables interconnected. Such a table is called a relation. A hierarchical database is a database in which information is ordered as follows: one element of the record is considered the main one, the rest are subordinate. A hierarchical database is formed by a file system on a disk, the generic genealogical tree of a Network database is called a database, in which horizontal links are added to vertical hierarchical links. Kolesova Zh.V.

Slide 7

DB STRUCTURE Each table must have its own name. A record is a table row. A field is a column in a table. The table is an information model of a real system. A record contains information about one specific object. The field contains certain characteristics of objects. The main element of the database is the record of Zh. V. Kolesov.

Slide 8

Table name field record The main key is a field or a set of fields that uniquely identifies a record in the table Zh. V. Kolesova.

Database (DB) - Database (DB) is a collection, in a certain way
organized information into some
topic.
For example:
Library book fund database;
Database of personnel of the institution;
Database of legislative acts in the region
criminal law;
Database of modern pop songs.

DB classification.

Databases are classified according to different criteria:
by the nature of the stored database information
divided into factual and
documentaries;
according to the method of storing database data, there are
centralized and distributed;
by the structure of the database organization
classified into relational
network and hierarchical.

In factual databases

contained brief information about
described objects, presented with
strictly defined format.
Examples:
1. In the library database about each book
the following information is stored: year
edition, author, title, etc.
2. In the database of the personnel department, personal information is stored
employee details: full name, year of birth and
etc.

Documentary DB

contains extensive information about
different types: text, graphic,
sound, multimedia.
Examples:
1. in the database of laws - the texts of the laws themselves,
2. in the pop song database - texts and notes
songs, biography of authors, information about
poets, composers and performers,
sound and video clips.

Information system

is a combination of the database and the entire complex
hardware and software for its
storage, modification and retrieval
information to interact with
user.
Examples:
1. Ticketing systems for
passenger trains and aircraft.
2. WWW is a global information
system.

Database (DB)

is a structured collection
interrelated data within
some subject area
designed for long
storage in external memory
computer and permanent
applications.

Can be used for database storage
to one computer, such a database
called centralized.
If different parts of the same database
stored on multiple computers
interconnected by a network,
such a database is called
distributed database.

A hierarchical database is called

in which information is organized
as follows: one element
records are considered the main, the rest
subordinates.
Examples: file system

Family tree

The network is called the database,

in which to vertical bonds
horizontal links are added.

Relational databases

- databases with tabular form
organization of information.
A relational database consists of one or
several interconnected
two-dimensional tables.

Examples:

In relational (table) databases, a row is called a record, and a column is called a field.

Fields are different characteristics
(sometimes called attributes) of an object.
Field values in one line
belong to the same object.
Different fields have different names.

Example 1. Organization of information in a single-table database "Repertoire of cinemas for the week".

Cinema
movie
Russia
Adventure 11.00
Pinocchio
Titanic
13.00
3.00
Russia
Russia
Titanic
Star
landing
17.00
21.00
20.00
15.00
World
Wait for it!
11.00
3.00
World
Titanic
13.00
15.00
World
Thief
17.00
10.00
Russia
time
price
15.00

Primary (master) key of the database

is a field or group of fields, with
through which it is possible to clearly
identify the entry. Meaning
primary key should not
repeat across records. IN
the example above in
as the primary key of the database
take a group of fields
cinema + time.

Field type

defines a set of values,
which can be accepted by this
field in different records.
In relational databases
four main types are used
fields: numeric, character,
date, boolean

The numeric type has fields whose values
can only be numbers. Numbers can be
whole and real.
Character type have fields in which there will be
store character sequences
(words, texts, codes, etc.).
The "date" type has fields containing
calendar dates in different form.
The boolean type corresponds to the field that
can only take two values:
"yes" - "no" or "true" - "false".

Example 2. Describe the structure of the database "Repertoire of cinemas for the week".

To describe the structure means to specify everything
table fields and their characteristics.
field name
type
width
cinema
symbolic
15
movie
symbolic
25
time
numerical
5
2
price
numerical
5
2
quantity
decimal
signs

Example 3. Given a fragment of a relational database: Specify the main key; describe the characteristics of the fields.

Number Date
departure flight
2156
Type
Price
plane ticket
23.10.08 TU-154
4564.50
Availability
tickets
Yes

Master key: flight number + date of departure. Field descriptions:

field name
type
width
Flight number
numerical
4
departure date
date
aircraft type
symbolic
10
Ticket price
numerical
5
Availability
tickets
logical
Qty
decimal
signs
2

Example 4. Convert to tabular form the hierarchical structure shown in fig.

Example 4. Convert to tabular form hierarchical
the structure shown in Fig.
department
faculty
university
general physics
Physical
PSU
theoretical physics
Physical
PSU
organic chemistry
Chemical
PSU
inorganic chemistry
Chemical
PSU
botany
Biological
PSU
zoology
biological
PSU

Task #1

Transform
below
information to
table view,
defining the table name and
the name of each field:
Olya, Petya, 13, singing, 14,
basketball, Vasya, Katya,
13, hockey, basketball,
football, 15.11, Kolya, 11,
dancing, Seryozha.
Table name: Employment in
mugs
Name
age circle
Olya
13
Singing
Peter
14
Basketball
Vasya
13
Hockey
Kate
15
Basketball
Kolya
11
Football
Series 11
dancing

Do it yourself:

1.
The database table "Patient" contains
fields: last name, first name, patronymic, date
birth, lot number, address,
presence of chronic diseases, date
last visit to the doctor.
Determine the type and width of each

Informatics lesson in grade 8 (I.G. Semakin)

Place of work, position: MOU "Secondary School No. 27", Syktyvkar, computer science teacher Vasily Yuryevich Petrov.

Region: Komi Republic

Level of education: basic general education

Class(es): Grade 8

Subject(s): Informatics

The purpose of the lesson: To get acquainted with the concept of a database, their types, organization.

Lesson type: Lesson learning new material.

Students per class: 10-20

Equipment used: computer, projector, slides.

Lesson outline.

Topic: The concept of an information system, database, DBMS.

The purpose of the lesson: to get acquainted with the types of databases and the organization of data in them.

Tasks:

1. Educational

Learn to distinguish between database types;

Give the technique of reading tables as relational databases.

2. Educational

Develop interest in structuring information;

To develop the analytical thinking of children, their creative abilities, the ability to work with various kinds of information.

3. Educational

Cultivate diligence, perseverance, patience.

4. Learner-centered

Creating situations of communication in the classroom, allowing each student to show initiative, independence.

Equipment: computer, projector.

Software part: presentation Microsoft Office power point.

Plan:

Organizing time.

Analysis of the studied material.

Message about the topic and purpose of the lesson.

Conversation.

Outcome.

During the classes

Organizing time.

Prepared notebooks, pens, drew attention to the board.

Analysis of the studied material.

Before we proceed to the topic of the lesson, let's remember what we studied in the previous lesson. Answer: information models: tabular, graphic, etc. You and I analyzed them on our own, without using computer technology. Modern means allow you to process data on a computer in large volumes.

Message about the topic and purpose of the lesson.

Let's talk about databases. (Slide #1)

Main conversation

Let's talk about structuring information, its collection and storage (Slide No. 2).

The processing of information using computer technology will be called information system. (Slide number 3).

We give the concept of a DATABASE, taking into account the available information (Slide No. 4).

Let's classify databases by types. We include students in the work through direct communication (Slide No. 5). Discussion.

We study in detail each type of database (Slides No. 6,7,8).

We get acquainted with relational databases, remember tabular information models (slide No. 9).

We turn to the key of relational databases. We are talking about the uniqueness of each entry (slide number 10).

We recall the types of information in the form of presentation and talk about what data we can store in databases (Slide No. 11).

7. The results of the lesson. (slide 19.20)

Our lesson is coming to an end. You did such a good job today! What do you remember? What have you learned?

List of sources used

Informatics: textbook for grade 8 / I.G. Semakin, L.A.

Introduction to databases
PPTX / 2.43 Mb
Zalogova, s.v. Rusakova, L.V. Shestakova. - 2nd ed., corrected. - M. : BINOM. Knowledge Laboratory, 2014. - 176 p. : ill.

The concept of DBMS -

Municipal Autonomous General Educational Institution

"Miass Secondary School No. 16"

Presentation

in computer science for grade 9

on the topic of:

Informatics teacher, 1st category

Shavaleeva Svetlana Alekseevna

Miass

DATABASE.

INFORMATION SYSTEM- this is a combination of a database and the entire complex of hardware and software for its storage, modification and information retrieval for user interaction

DATABASE MANAGEMENT SYSTEM (DBMS) Software designed to work with databases

DATABASE (DB)

DATABASES AND INFORMATION SYSTEMS

DATABASE (DB)

An organized collection of data intended for long-term storage in the external memory of a computer and permanent use

FACTOGRAPHIC

Brief information about objects in a well-defined format

DOCUMENTARY

DISTRIBUTED DB

Documents in various formats

Storing different parts of the same database on multiple computers connected by a network.

text information
graphic objects
sound information
multimedia objects
. . . . . . . . . . . . . . . . . .

library directory
personnel database
reference file
. . . . . . . . . . . . . . . .

Hierarchical model

In a hierarchical model, the structure of information is in the form of a tree. At the topmost (first) level, there is only one vertex, which is called the root. This vertex has connections with the vertices of the second level, the vertices of the second level have connections only with the vertices of the third level, and so on.

In the network model, the main structure representation of information is in the form of a network, in which each vertex can have a connection with any other.

In relational model information is presented in the form of a table. The rows of the table are records, and the columns are the same fields.

DATABASE MANAGEMENT SYSTEMS

DBMS - application program, designed to work with the database.

DBMS - software, providing access to information stored in the database, its maintenance and processing.

DBMS examples:

KBASE, FOXPRO, VISTA, RBDMSX, ACCESS.
KBASE,
foxpro,
VISTA,
RBDMSX,
ACCESS.

DATA TYPES

1) Text - the value of a text data is represented by a set of alphanumeric characters. The length of text data does not exceed 255 characters. Default, Microsoft Access sets the length to 50 characters. Specifying the length of a text field means that if you try to type more than long text extra characters will be ignored. If the text field contains numeric data, then this data is treated as text, and in mathematical operations cannot participate.

Text data type

DATA TYPES

2) Counter - used for automatic numbering of records.

Data type "Counter"

DATA TYPES

3) Numerical - used for data (integer and fractional) involved in calculations.

Numeric data can be in any of the following formats:

Meaning

Description

Byte

Numbers from 0 to 255 (no fractional part)

Whole

Fraction

long integer

Numbers from -32768 to 32767 (no fractional part)

Absent

Size

1 byte

(Default value). Numbers from -2147483648 to 2147483647

(without fractional part)

Absent

floating point (4 bytes)

floating point (8 bytes)

Numbers from

-3.402823* to 3.402823*

Absent

2 bytes

4 bytes

Numbers from

-1.79769313486232* to 1.79769313486232*

Replication Code

4 bytes

Globally Unique Identifier (GUID)

8 bytes

Undefined

16 bytes

DATA TYPES

4) Date / Time- used to store time or date. It is possible to perform calculations with data (calculate the time interval between individual dates).

Date data type

DATA TYPES

5) Money - almost the same as the numeric type, but with a fixed number of decimal places and a currency sign.

DATA TYPES

6) Boolean fields - are used to store data that can take one of two possible values: True / Lie , Yes / No or On off. At the same time, the values True , Yes And On True, and the values Lie , No And Off equivalent to boolean False .

DATA TYPES

7) Fields OLE object - allows you to store images and other binary data in tables (for example, a spreadsheet Microsoft excel, document Microsoft Word , drawing, sound recording).

DATA TYPES

9) Field MEMO - arbitrary length text fields can contain the same data types as simple text fields. The difference between these fields is that the size of the field MEMO is not limited to 255 characters, but can contain up to 65535 characters.

DATA TYPES

10) Lookup master data type - is designed to create a field that offers a choice of values from a drop-down list containing a set of constant values or values from another table.

FIELD TYPES IN RELATIONAL DATABASES

Field type defines the set of values that this field can take in different records

numerical

symbolic

date Time

logical

These fields are for storing calendar dates and time of day data.

Date: "day / month / year"

Time watch : minutes »

Field value can only be a number

These fields store character sequences (words, texts, etc.)

Database "Electives"

Time Tracking Database

Last name, first name

Ivanov Petya

Petrov Vanya

time tracking

Sidorov Victor

Time spent

numerical

symbolic

logical

Access 2007 objects

tables- basic database objects.

Requests are special structures designed to process database data.

Forms- These are objects with the help of which new data is entered into the database or existing ones are viewed.

Reports- these are forms "on the contrary", With their help, data is issued to the printer in a convenient and visual form.

Macros - This macros.

Modules are programs written in Visual language basic.

Working Modes with Access 2007

In working with any database, there are two different modes: design - using the constructor

And operational(custom) - using the wizard.