Where clause is used to filter the data based on the criteri provided. Having clause is also used to filter data but the only difference is where clause is applied for each row and having clause is applied for group.having clause specifies a search condition for a group or an aggregrate function used in select statement. You can use both where clause and having clause in a select statement.For example, I want to query book ids, average of book price for all the books where the author's city is Philly and the data should be group by product id having average price more than $50.