Rdbms Notes
1
RELATIONAL DATABASE MANAGEMENT SYSTEM
UNIT-1
INTRODUCTION:DATA :- Data is a collection of facts, which is in unorganized but they can be organized into useful form. Data is of two types :1.Raw Data :- It is a Data which are collected from different sources and has no meaning. ` 2. Derived Data :- It is a data that are extracted from Raw Data and used for getting useful information. Derived Data is called as INPUTDATA. INPUT DATA is processed to get the OUTPUT data. The OUTPUT DATA is called as INFORMATION. The database today may contain either data or information. The term data and information are closely related.
INPUT DATA PROCESSING OUTPUT DATA
Proccessing of data is called Data Proccessing. Proccessing of Data in an electronic device i.e computer is called “Electronic Data Proccessing” Meta data: Data that describe the properties or characteristics of other data. Some of these properties include data definition,data or characteristics of other Data,Data Structures,Rules or constraints. Ex:- Datatype : integer,Character,float… Size :- 9,10,…(size of the field) Constraint :- Primary Key
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2
DataBase : A Database is a collection of interrelated data. A DataBase is a logically coherent collection of Data with some inherent meaning. A Database is designed, built and populated with data for a specific purpose. A Database can be of any size and of varying complexity DATABASE MANAGEMNT SYSTEM (DBMS) :- DBMS is a collection of programs that enables users to create and maintain a database. The dbms is Hence a general-purpose s/w system that facilitates the process of defining, constructing and manipulating databases for various applications. TRADITIONAL FILE PROCESSING:File:- File is collection of records Record: - Record is collection of field’s data. Fields: - Field is a characteristic of a particular data item. or Data. ex:- Filename :- student Fields:- studno, studname, sub1,sub2,sub3…… Record: - 123, abc, 76, 98, 90… File
RELATIONAL DATABASE MANAGEMENT SYSTEM
UNIT-1
INTRODUCTION:DATA :- Data is a collection of facts, which is in unorganized but they can be organized into useful form. Data is of two types :1.Raw Data :- It is a Data which are collected from different sources and has no meaning. ` 2. Derived Data :- It is a data that are extracted from Raw Data and used for getting useful information. Derived Data is called as INPUTDATA. INPUT DATA is processed to get the OUTPUT data. The OUTPUT DATA is called as INFORMATION. The database today may contain either data or information. The term data and information are closely related.
INPUT DATA PROCESSING OUTPUT DATA
Proccessing of data is called Data Proccessing. Proccessing of Data in an electronic device i.e computer is called “Electronic Data Proccessing” Meta data: Data that describe the properties or characteristics of other data. Some of these properties include data definition,data or characteristics of other Data,Data Structures,Rules or constraints. Ex:- Datatype : integer,Character,float… Size :- 9,10,…(size of the field) Constraint :- Primary Key
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2
DataBase : A Database is a collection of interrelated data. A DataBase is a logically coherent collection of Data with some inherent meaning. A Database is designed, built and populated with data for a specific purpose. A Database can be of any size and of varying complexity DATABASE MANAGEMNT SYSTEM (DBMS) :- DBMS is a collection of programs that enables users to create and maintain a database. The dbms is Hence a general-purpose s/w system that facilitates the process of defining, constructing and manipulating databases for various applications. TRADITIONAL FILE PROCESSING:File:- File is collection of records Record: - Record is collection of field’s data. Fields: - Field is a characteristic of a particular data item. or Data. ex:- Filename :- student Fields:- studno, studname, sub1,sub2,sub3…… Record: - 123, abc, 76, 98, 90… File