What is basic SELECT statement?

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SELECT Statement
A SELECT statement retrieves data from the database. With SELECT statement PROJECTION, SELECTION and JOIN can be performed on database tables.
As data in relational database is stored in TABLES. TABLE has ROW and COLUMN structure. With SELECT statement all rows and all columns can be retrieved, this is known as PROJECTION. But, if rows and columns are retrieved on the basis of some condition, it is known as SELECTION. And suppose if some information is needed and that is stored in two or more different tables but are related, use JOINS to retrieve it from two or more tables.
In SQL, basic SELECT statements are as follows:
SELECT * FROM [table_name];
SELECT[column1][column2][column3],..... FROM  [table_name];
SELECT and FROM are known as clauses. 
SELECT clause allows to specify columns to be selected from the database table. 
FROM clause allows to specify table name that has those column to be selected.
Semicolon at the end of SELECT statement specify the end of SQL statemen…

What is database and database management system (DBMS) ?

Data

Data can be defined as a known fact that has some meaning. For example you have your first name and last name, your aadhar number, your mobile number, your PAN etc. all these are data.

Database

The logical collection of all the related data is known as database.Database can be maintained at individual or organizational level depending upon on the requirements. At individual it can be of smaller size but at organizational level it can be of complex and huge in size. 

For example you store all your contacts in your mobile, it is a collection of contact numbers in your mobile only but if we talk about Flipkart, it is an example of organizational level database that has large collection of consumer products like clothing, electronics, furniture, books etc.

Database Management System

Database Management System is a set of programs that allows to create and maintain a database. It provides a process to store and access the data in an efficient and systematic way. This process includes defining the structure, type and constraints of the data to be stored. It also ensures the security and long term maintainability of the data.

Examples of DBMS are:
MySQL, MS SQL Server, Oracle Database, IBM DB2, Postgre SQL etc..



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