SQL HAVING Clause-tutorial
SQL HAVING Clause
- The HAVING clause in SQL is used in conjunction with the GROUP BY clause to filter the results of a query based on a specified condition.
Syntax:
SELECT column1, aggregate_function(column2)
FROM table_name
GROUP BY column1
HAVING condition;
- column1: The column(s) by which you are grouping the results.
- aggregate_function(column2): An aggregate function (e.g., SUM, COUNT, AVG, etc.) applied to another column (column2).
- condition: The condition that the aggregated results must satisfy.
Example:
Employee table
Emp_ id | Emp _ name | working_ date | working_ hours |
1 | Ajeet | 2015-01-24 | 12 |
2 | Ayan | 2015-01-24 | 10 |
3 | Milan | 2015-01-25 | 9 |
1 | Ayan | 2015-01-25 | 6 |
2 | Ajeet | 2015-01-25 | 4 |
we use the SUM function with the HAVING Clause to return the emp_ name and sum of their working hours.
SELECT emp_ name, SUM(working_ hours) AS "Total working hours"
FROM employees
GROUP BY emp_ name
HAVING SUM(working_ hours) > 5;output:
emp_ name | Total working_ hours |
Ajeet | 16 |
Ayan | 16 |
Milan | 9 |