The SQL WHERE clause is used to filter records during selecting records from one or more tables in SQL. If the condition specified in the WHERE clause matches then only the SQL query returns the specific value. You can use WHERE clause only to filter the necessary records while rest of the unwanted records will be discarded.

The WHERE clause not only used in the SELECT statement but also used in the UPDATE and DELETE statement.

SQL WHERE Clause Syntax

The basic syntax of WHERE clause along with the SELECT statement is as below.

 SELECT column1, column2, columnN 
FROM table_name
WHERE [condition]

In this syntax,

  • column1, column2, columnN – The names of the column from table.
  • table_name – The name of the table from which data need to be fetched.
  • WHERE [condition] – This is used to specify some conditions while selecting data. In case you are not using WHERE clause all the rows available will be selected.

You can specify a condition in the WHERE clause using the comparison or logical operators like >, <, =, LIKE, NOT, etc. 

SQL WHERE Clause Example

Consider a table of Employee with the following records.

emp_id emp_name emp_gender emp_salary dept_code emp_location
1510 Avinash M 33000 101 Mumbai
1511 Ramjan M 56000 105 Kolkata
1512 Piyanka F 35000 103 Kolkata
1513 Piyam M 42000 101 Kolkata
1514 Jitu M 43000 104 Mumbai
1515 Raman M 49000 105 Delhi
1516 Lata F 27000 104 Mumbai
1517 Prakash M 45000 101 Delhi
1518 Nitu F 45000 103 Mumbai
1519 Pallab M 42000 103 Kolkata
1520 Pankaj M 55000 101 Bangalore

The following example fetch the emp_id, emp_name, emp_salary  from the Employee table whose salary is 45000 or more:

SELECT emp_id, emp_name, emp_salary
FROM Employee
WHERE emp_salary >= 45000
ORDER BY emp_id;
emp_id emp_name emp_salary
1511 Ramjan 56000
1515 Raman 49000
1517 Prakash 45000
1518 Nitu 45000
1520 Pankaj 55000

In the following example, the SQL query will fetch emp_id, emp_name and emp_salary from the Employee table where emp_name is "Prakash".

One thing you have to remember that if you are providing a string value in the WHERE clause it should be enclosed with single quotes(”). Whereas for numeric should not be inside any quotes as seen the above example.

SELECT emp_id, emp_name, emp_salary
FROM Employee
WHERE emp_salary = 'Prakash';
emp_id emp_name emp_salary
1517 Prakash 45000

Summary: In this tutorial, you have learned how to use SQL WHERE clause to filter out the records while select data from one more tables.