HAVING clause enables you to specify conditions that filter which group results appear in the final results.
The WHERE clause places conditions on the selected columns, whereas the HAVING clause places conditions on groups created by GROUP BY clause.
Following is the position of HAVING clause in a SELECT query.
SELECT FROM WHERE GROUP BY HAVING ORDER BY
HAVING clause must follow GROUP BY clause in a query and must also precede ORDER BY clause if used. Following is the syntax of the SELECT statement, including HAVING clause.
SELECT column1, column2 FROM table1, table2 WHERE [ conditions ] GROUP BY column1, column2 HAVING [ conditions ] ORDER BY column1, column2
Consider COMPANY table with the following records.
ID NAME AGE ADDRESS SALARY ---------- ---------- ---------- ---------- ---------- 1 Paul 32 California 20000.0 2 Allen 25 Texas 15000.0 3 Teddy 23 Norway 20000.0 4 Mark 25 Rich-Mond 65000.0 5 David 27 Texas 85000.0 6 Kim 22 South-Hall 45000.0 7 James 24 Houston 10000.0 8 Paul 24 Houston 20000.0 9 James 44 Norway 5000.0 10 James 45 Texas 5000.0
Following is the example, which will display the record for which the name count is less than 2.
sqlite > SELECT * FROM COMPANY GROUP BY name HAVING count(name) < 2;
This will produce the following result.
ID NAME AGE ADDRESS SALARY ---------- ---------- ---------- ---------- ---------- 2 Allen 25 Texas 15000 5 David 27 Texas 85000 6 Kim 22 South-Hall 45000 4 Mark 25 Rich-Mond 65000 3 Teddy 23 Norway 20000
Following is the example, which will display the record for which the name count is greater than 2.
sqlite > SELECT * FROM COMPANY GROUP BY name HAVING count(name) > 2;
This will produce the following result.
ID NAME AGE ADDRESS SALARY ---------- ---------- ---------- ---------- ---------- 10 James 45 Texas 5000