SQLite Group By
The GROUP BY clause in SQLite is used with the SELECT statement to group identical data.
In the SELECT statement, the GROUP BY clause is placed after the WHERE clause and before the ORDER BY clause.
Syntax
The basic syntax of the GROUP BY clause is given below. The GROUP BY clause must be placed after the conditions of the WHERE clause and must be placed before the ORDER BY clause.
SELECT column-list
FROM table_name
WHERE [ conditions ]
GROUP BY column1, column2....columnN
ORDER BY column1, column2....columnN
You can use multiple columns in the GROUP BY clause. Ensure that the grouping columns are included in the column list.
Example
Suppose the COMPANY table has 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
If you want to know the total salary for each customer, you can use a GROUP BY query as follows:
sqlite> SELECT NAME, SUM(SALARY) FROM COMPANY GROUP BY NAME;
This will produce the following result:
NAME SUM(SALARY)
---------- -----------
Allen 15000.0
David 85000.0
James 10000.0
Kim 45000.0
Mark 65000.0
Paul 20000.0
Teddy 20000.0
Now, let's create three additional records in the COMPANY table using the following INSERT statements:
INSERT INTO COMPANY VALUES (8, 'Paul', 24, 'Houston', 20000.00 );
INSERT INTO COMPANY VALUES (9, 'James', 44, 'Norway', 5000.00 );
INSERT INTO COMPANY VALUES (10, 'James', 45, 'Texas', 5000.00 );
Now, our table has records with duplicate names, as shown below:
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
Let's use the same GROUP BY statement to group all records by the NAME column, as shown below:
sqlite> SELECT NAME, SUM(SALARY) FROM COMPANY GROUP BY NAME ORDER BY NAME;
This will produce the following result:
NAME SUM(SALARY)
---------- -----------
Allen 15000
David 85000
James 20000
Kim 45000
Mark 65000
Paul 40000
Teddy 20000
Let's use the ORDER BY clause along with the GROUP BY clause, as shown below:
sqlite> SELECT NAME, SUM(SALARY)
FROM COMPANY GROUP BY NAME ORDER BY NAME DESC;
This will produce the following result:
NAME SUM(SALARY)
---------- -----------
Teddy 20000
Paul 40000
Mark 65000
Kim 45000
James 20000
David 85000
Allen 15000