Differences between where clause and having clause

Where clause	Having clause
Both where and having clause can be used to filter the data.
Where as in where clause it is not mandatory.	But having clause we need to use it with the group by.
Where clause applies to the individual rows.	Where as having clause is used to test some condition on the group rather than on individual rows.
Where clause is used to restrict rows.	But having clause is used to restrict groups.
Restrict normal query by where	Restrict group by function by having
In where clause every record is filtered based on where.	In having clause it is with aggregate records (group by functions).

Order of where and having:

SELECT column, group_function

FROM table

[WHERE condition]

[GROUP BY group_by_expression]

[HAVING group_condition]

[ORDER BY column];

The WHERE clause cannot be used to restrict groups. you use the

HAVING clause to restrict groups.