Database Management System
Introduction to the course
This course is first (fundamental) course on database management systems. The course
discusses different topics of the databases. We will be covering both the theoretical and
practical aspects of databases. As a student to have a better understanding of the subject,
it is very necessary that you concentrate on the concepts discussed in the course.
Areas to be covered in this Course:
* Database design and application development: How do we represent a real-world
system in the form of a database? This is one major topic covered in this course. It
comprises of different stages, we will discuss all these stages one by one.
* Concurrency and robustness: How does a DBMS allow many users to access data
concurrently, and how does it protect against failures?
* Efficiency and Scalability: How does the database cope with large amounts of data?
discusses different topics of the databases. We will be covering both the theoretical and
practical aspects of databases. As a student to have a better understanding of the subject,
it is very necessary that you concentrate on the concepts discussed in the course.
Areas to be covered in this Course:
* Database design and application development: How do we represent a real-world
system in the form of a database? This is one major topic covered in this course. It
comprises of different stages, we will discuss all these stages one by one.
* Concurrency and robustness: How does a DBMS allow many users to access data
concurrently, and how does it protect against failures?
* Efficiency and Scalability: How does the database cope with large amounts of data?
* Study of tools to manipulate databases: In order to practically implement, that is, to
perform different operations on databases some tools are required. The operations
on databases include right from creating them to add, remove and modify data in
the database and to access by different ways. The tools that we will be studying are
a manipulation language (SQL) and a DBMS (SQL Server).
perform different operations on databases some tools are required. The operations
on databases include right from creating them to add, remove and modify data in
the database and to access by different ways. The tools that we will be studying are
a manipulation language (SQL) and a DBMS (SQL Server).
Database definitions:
Definitions are important, especially in technical subjects because definition describes
very comprehensively the purpose and the core idea behind the thing. Databases have
been defined differently in literature. We are discussing different definitions here, if we
concentrate on these definitions, we find that they support each other and as a result of
the understanding of these definitions, we establish a better understanding of use,
working and to some extent the components of a database.
Def 1: A shared collection of logically related data, designed to meet the information
needs of multiple users in an organization. The term database is often erroneously
referred to as a synonym for a “database management system (DBMS)”. They are
not equivalent and it will be explained in the next section.
Def 2: A collection of data: part numbers, product codes, customer information, etc. It
usually refers to data organized and stored on a computer that can be searched and
retrieved by a computer program.
Def 3: A data structure that stores metadata, i.e. data about data. More generally we can
say an organized collection of information.
Def 4: A collection of information organized and presented to serve a specific purpose.
(A telephone book is a common database.) A computerized database is an updated,
organized file of machine readable information that is rapidly searched and
retrieved by computer.
Def 5: An organized collection of information in computerized format.
Def 6: A collection of related information about a subject organized in a useful manner
that provides a base or foundation for procedures such as retrieving information,
drawing conclusions, and making decisions.
Def 7: A Computerized representation of any organizations flow of information and
storage of data.
Each of the above given definition is correct, and describe database from slightly variant
perspectives. From exam point of view, anyone will do. However, within this course, we
will be referring first of the above definitions more frequently, and concepts discussed in
the definition like, logically related data, shared collection should be clear. Another
very comprehensively the purpose and the core idea behind the thing. Databases have
been defined differently in literature. We are discussing different definitions here, if we
concentrate on these definitions, we find that they support each other and as a result of
the understanding of these definitions, we establish a better understanding of use,
working and to some extent the components of a database.
Def 1: A shared collection of logically related data, designed to meet the information
needs of multiple users in an organization. The term database is often erroneously
referred to as a synonym for a “database management system (DBMS)”. They are
not equivalent and it will be explained in the next section.
Def 2: A collection of data: part numbers, product codes, customer information, etc. It
usually refers to data organized and stored on a computer that can be searched and
retrieved by a computer program.
Def 3: A data structure that stores metadata, i.e. data about data. More generally we can
say an organized collection of information.
Def 4: A collection of information organized and presented to serve a specific purpose.
(A telephone book is a common database.) A computerized database is an updated,
organized file of machine readable information that is rapidly searched and
retrieved by computer.
Def 5: An organized collection of information in computerized format.
Def 6: A collection of related information about a subject organized in a useful manner
that provides a base or foundation for procedures such as retrieving information,
drawing conclusions, and making decisions.
Def 7: A Computerized representation of any organizations flow of information and
storage of data.
Each of the above given definition is correct, and describe database from slightly variant
perspectives. From exam point of view, anyone will do. However, within this course, we
will be referring first of the above definitions more frequently, and concepts discussed in
the definition like, logically related data, shared collection should be clear. Another
important thing that you should be very clear about is the difference between database
and the database management system (DBMS). See, the database is the collection of data
about anything, could be anything. Like cricket teams, students, busses, movies,
personalities, stars, seas, buildings, furniture, lab equipment, hobbies, hotels, pets,
countries, and many more anything about which you want to store data. What we mean
by data; simply the facts or figures. Following table shows the things and the data
and the database management system (DBMS). See, the database is the collection of data
about anything, could be anything. Like cricket teams, students, busses, movies,
personalities, stars, seas, buildings, furniture, lab equipment, hobbies, hotels, pets,
countries, and many more anything about which you want to store data. What we mean
by data; simply the facts or figures. Following table shows the things and the data
There could be infinite examples, and please note that the data that is listed about
different things in the above table is not the only data that can be defined or stored about
these things. As has been explained in the definition one above, there could be so many
facts about each thing that we are storing data about; what exactly we will store depends
on the perspective of the person or organization who wants to store the data. For example,
if you consider food, data required to be stored about the food from the perspective of a
cook is different from that of a person eating it. Think of a food, like, Karhahi Ghost, the
facts about Karhahi ghosht that a cook will like to store may be, quantity of salt, green
and red chilies, garlic, water, time required to cook and like that. Where as the customer
is interested in chicken or meat, then black or red chilies, then weight, then price and like
that. Well, definitely there are some things common but some are different as well. The
thing is that the perspective or point of view creates the difference in what we store;
however, the main thing is that the database stores the data.
The database management system (DBMS), on the other hand is the software or tool that
is used to manage the database and its users. A DBMS consist of different components or
subsystem that we will study about later. Each subsystem or component of the DBMS
performs different function(s), so a DBMS is collection of different programs but they all
work jointly to manage the data stored in the database and its users. In many books and
may be in this course sometimes database and database management system are used
interchangeably but there is a clear difference and we should be clear about them.
Sometimes another term is used, that is, the database system, again, this term has been
used differently by different people, however in this course we use the term database
system as a combination of database and the database management system. So database is
collection of data, DBMS is tool to manage this data, and both jointly are called database
system.
to download this course click here
different things in the above table is not the only data that can be defined or stored about
these things. As has been explained in the definition one above, there could be so many
facts about each thing that we are storing data about; what exactly we will store depends
on the perspective of the person or organization who wants to store the data. For example,
if you consider food, data required to be stored about the food from the perspective of a
cook is different from that of a person eating it. Think of a food, like, Karhahi Ghost, the
facts about Karhahi ghosht that a cook will like to store may be, quantity of salt, green
and red chilies, garlic, water, time required to cook and like that. Where as the customer
is interested in chicken or meat, then black or red chilies, then weight, then price and like
that. Well, definitely there are some things common but some are different as well. The
thing is that the perspective or point of view creates the difference in what we store;
however, the main thing is that the database stores the data.
The database management system (DBMS), on the other hand is the software or tool that
is used to manage the database and its users. A DBMS consist of different components or
subsystem that we will study about later. Each subsystem or component of the DBMS
performs different function(s), so a DBMS is collection of different programs but they all
work jointly to manage the data stored in the database and its users. In many books and
may be in this course sometimes database and database management system are used
interchangeably but there is a clear difference and we should be clear about them.
Sometimes another term is used, that is, the database system, again, this term has been
used differently by different people, however in this course we use the term database
system as a combination of database and the database management system. So database is
collection of data, DBMS is tool to manage this data, and both jointly are called database
system.
to download this course click here
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