Hello, everyone if you familiar with the DBMS ( Data base management system) you can easily understand this. Data base management system is used for creating data , manipulation of information,and retrieving the data or store. The flat Data base system is a text Data base system. Because it’s a very important and useful type of data base in relational database management system. It is used for Store data inside the plain text file ( Ms Excel).This is developed by IBM company in the year 1970. The relational database over flat file system is mostly used to create Data base.
–What do you mean by RDBMS?
RDBMS is a Data base management system based on relational model is called relational database management system or RDBMS. A relational model consists of Two- dimensional Data structure,to store data, manipulation or retrieving. Each relations has a set of attributes to describe the properties of Data contained in it, and for each attributes,a relation has related data in the form of Tuples ( or rows).
Table- A students relation.
Roll_ No. Name No. 1001 Abhishek. 92 1002 Deepak. 81 1003 Narendra. 95 1004 Abhilash. 80
in this a student relation as a structure which has attributes Roll_ No, Name ,and No with four row. A relation is also called a table and the attributes are called column.
Advantage of RDBMS-
- Data integrity
- Data redundancy
- Data consistency
A Database is divided into logical storage unit called tablespaces, with the following characteristics-
- Each database is divided into one or more table- spaces.
- There is a system table space and users table space.
- One or more data file are created in each table- space. A data file can be associated with only one databases.
- The combined storage capacity of a database systems table space is total storage capacity of the database.
Oracle database is made up of set of a physical files that reside on the host server’s disk drivers. Some of these files, Such as the data files,redo log files, and control files, maintain the state of the database object’s . Text- based alert and trace file contains logging information for both routine event and error conditions in the database.
These physical files are discussed below-
- Data files
- Redo log files
- Control files
- Archived log files
- Initialisation parameters files
- Alert and trace log files
- Backup file.