SELECT Query

SELECT Query
Select query is used to retrieve data from a tables. It is the most used SQL query. We can retrieve complete tables, or partial by mentioning conditions using WHERE clause.

Syntax of SELECT Query

SELECT column-name1, column-name2, column-name3, column-nameN from table-name;
Example for SELECT Query

Conside the following Student table,

S_id S_Name age address
101 Adam 15 Noida
102 Alex 18 Delhi
103 Abhi 17 Rohtak
104 Ankit 22 Panipat
SELECT s_id, s_name, age from Student.
The above query will fetch information of s_id, s_name and age column from Student table

S_id S_Name age
101 Adam 15
102 Alex 18
103 Abhi 17
104 Ankit 22
Example to Select all Records from Table

A special character asterisk * is used to address all the data(belonging to all columns) in a query. SELECT statement uses * character to retrieve all records from a table.

SELECT * from student;
The above query will show all the records of Student table, that means it will show complete Student table as result.

S_id S_Name age address
101 Adam 15 Noida
102 Alex 18 Delhi
103 Abhi 17 Rohtak
104 Ankit 22 Panipat
Example to Select particular Record based on Condition

SELECT * from Student WHERE s_name = 'Abhi';
103 Abhi 17 Rohtak
Example to Perform Simple Calculations using Select Query

Conside the following Employee table.

eid Name age salary
101 Adam 26 5000
102 Ricky 42 8000
103 Abhi 22 10000
104 Rohan 35 5000
SELECT eid, name, salary+3000  from Employee;
The above command will display a new column in the result, showing 3000 added into existing salaries of the employees.

eid Name salary+3000
101 Adam 8000
102 Ricky 11000
103 Abhi 13000
104 Rohan 8000