How To Apply Filtering Criteria at Group Level

Q

How To Apply Filtering Criteria at Group Level? - Oracle DBA FAQ - Understanding SQL SELECT Query Statements

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A

If you want to return only specific groups from the query, you can apply filtering criteria at the group level by using the HAVING clause inside the GROUP BY clause. The following script gives you a good HAVING example:

SQL> SELECT department_id, MIN(salary), MAX(salary), 
  2  AVG(salary) FROM employees GROUP BY department_id
  3  HAVING AVG(salary) < 5000;
DEPARTMENT_ID MIN(SALARY) MAX(SALARY) AVG(SALARY)
------------- ----------- ----------- -----------
           30        2500       11000        4150
           50        2100        8200  3475.55556
           10        4400        4400        4400

2007-04-20, 4574👍, 0💬

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