Prabhat Sahu

 Profile Answers by Prabhat Sahu 

• Oct 12th, 2018

 

Implicit properties of Relational Database.

An RDBMS is easily accessible using Structured Query Language (SQL) commands in them to manipulate data.
SQL is the ISO standard language for interacting with a RDBMS.
An RDBMS provides full data independence.
The organization of the data is independent of the applications that using it.
You do not need to specify the access routes of the data source/tables from where your SQL query is going to fetch data from.
Also You do not need to know how data is physically arranged in a database.
The basic unit of data storage in a relational database is called a table.
A table consists of Tuples/rows/records and each record have one or more number of columns used to store values.
For access purpose, the order of rows and columns is insignificant. You can control the access order as required.
When querying the database, you use conditional operations such as joins and restrictions.
A join combines data from separate database rows and a restriction limits the specific rows returned by a query.
An RDBMS enables data sharing between users. At the same time, you can ensure consistency of data across multiple tables by using integrity constraints. An RDBMS uses various types of data integrity constraints.

These types include
entity integrity constraint,
column integrity constraint,
referential integrity constraint,
user- defined constraints

The entity integrity constraint, ensures uniqueness of rows,
The column integrity ensures consistency of the type of data within a column.
The referential integrity ensures validity of foreign keys within a table or in between 2 separate tables
and The user-defined constraints are used to enforce the specific business rules.
An RDBMS minimizes the redundancy of data.
This means that similar data is not repeated in multiple tables. Or if it repeated it should be minimal with specific purpose.