SQL Select

The SQL SELECT Statement

The SELECT statement is used to select data from a database.

SQL SELECT Syntax

SELECT column_name,column_name
FROM table_name;

Ex.

SELECT * FROM TABLE_NAME

Note - This Query select All data in table from database.

SQL SELECT DISTINCT

The SELECT DISTINCT statement is used to return only distinct (different) values.

In a table contain many duplicate values. and sometimes you only want to list the different (distinct) values.
The DISTINCT keyword can be used to return only distinct (different) values.

SQL SELECT DISTINCT Syntax

SELECT DISTINCT column_name

FROM table_name

The following SQL statement selects only the distinct values from the "Name" columns from the "Master" table:

Example

SELECT DISTINCT Name FROM Master; 

The SQL WHERE

In Sql Select Query you want to apply Where condition then use this query and give condition whatever you want to apply. like example

Syntax

SELECT column1,column2 FROM TableName WHERE column_name operator value;

Example

Select EmpName,Salary from Employe

EmpName	Salary
Jeet	30000
Ranu	15000
Pulkit	10000
Vijay	12000

Note - In This Select query select EmpName & Salary column name from Employe table ,execute this query then get all EmpName and according salary in Employe table, but You want those record according particular Empname and salary based then you apply where condition. like

Example

Select EmpName,Salary from Employe where Salary > 15000
Output-
Note- Filter according where condition and get result

EmpName	Salary
Jeet	30000

SQL ORDER BY

Select Query and you want to sort result by one or more columns then use order by in query like in example

Syntax

SELECT column1,column2 FROM TableName ORDRE BY column_name ASC|DESC

Example

SELECT EmpName,Salary from Employe ORDER BY EmpName DESC

EmpName	Salary
Vijay	12000
Ranu	15000
Pulkit	10000
Jeet	30000

Note-In this example record sort by descending ordre by EempName. if you not give DESC keyword then sorts the records in ascending order by default,

SQL AND & OR Operators

In this artical describe The AND & OR operators. This operators are used to filter records based on more than one condition. AND Operator- Apply this Operator displays a record if both the first condition AND the second condition are true.Both condition are mandatory true

Syntax

SELECT column1,column2 FROM TableName WHERE Condition1 AND condition2

Example

Select EmpName,Salary from Employe where Salary > 15000 AND Salary = 30000
Output-
Note- Filter according where condition and get result

EmpName	Salary
Jeet	30000

Notes - In this example both condition true salary is grater then 15000 and equal to 30000 both condition match and return result So we use and condition

OR Operator

OR Operator- Apply this Operator displays a record if either the first condition AND the second condition is true.

Example

Select EmpName,Salary from Employe where Salary > 15000 OR Salary < 40000
Output-
Note- Filter according where condition and get result

EmpName	Salary
Jeet	30000

Note- Apply OR condition where salary is greater then 15000 and less then 40000 and return sql result.

Combining AND & OR

You can also combine AND and OR (use parenthesis to form complex expressions).

Example

Select EmpName,Salary from Employe where EmpName='Jeet' AND (Salary > 15000 OR Salary < 40000)
Output-
Note- Filter according where condition and get result

EmpName	Salary
Jeet	30000

The following SQL statement selects all Employe record from the EmpName "Jeet" AND the Salary must be greater than to "15000" OR less than "40000", in the "Employe" table: