SQLite Group By
SQLite's GROUP BY clause is used with the SELECT statement to group the same 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 condition in the WHERE clause and before the ORDER BY clause.
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. Make sure the grouping you are using is listed in the column list.
Example
Assuming the COMPANY table has the following records:
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- ------- ----------- ---------- ----------
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 Jamest on 10000.0
If you want to know the total salary of each customer, you can use GROUP BY query, as shown below:
This will produce the following results:
---------- ---------- --
Allen 15000.0
David 85000.0
James 10000.0
Kim 45000.0
Mark 65000.0
Paul 20000.0
Teddy 20000.0
Now, let’s Use the following INSERT statement to create three additional records in the COMPANY table:
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 follows:
1 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 Jameston 10000.0
8 PAUL 24 Houston 20000.0
9 James 44 Norway 5000.0
10 James 45 Texas 5000.0
Let us use the same GROUP BY statement to group all records by the NAME column as follows:
sqlite> SELECT NAME, SUM(SALARY) FROM COMPANY GROUP BY NAME ORDER BY NAME;
This will produce the following results:
---------- -----------
Allen 15000
David 85000
James 20000
Kim 45000
Mark 65000
Paul 40000
Teddy 20000
Let us use the ORDER BY clause with the GROUP BY clause as follows:
FROM COMPANY GROUP BY NAME ORDER BY NAME DESC;
This will produce the following results:
---------- -----------
Teddy 20000
Paul 40000
Mark 65000
Kim 45000
James 20000
David 85000
Allen 15000
