COUNT(), AVG(), SUM() Functions
The SQL COUNT(), AVG(), SUM() Functions used to calculate the specific values:
- The COUNT() function returns the number of ROWS that matches.
- The AVG() function used to calculate the average value of a numeric column.
- The SUM() function returns the total SUM of a numeric column.
Syntax of COUNT() function
SELECT COUNT (column_name)
FROM table_name
WHERE [condition];
Syntax of AVG() function
SELECT AVG (column_name)
FROM table_name
WHERE [condition];
Syntax of SUM() function
SELECT SUM (column_name)
FROM table_name
WHERE [condition];
Example of COUNT(), AVG(), SUM()
Sample Orders Table
| ORD_ID |
ORD_DATE |
ORD_AMOUNT |
ADVANCE_AMOUNT |
| 0210 |
10/01/2019 |
4000 |
1500 |
| 0211 |
10/22/2019 |
3500 |
500 |
| 0222 |
10/29/2019 |
1000 |
100 |
| 0225 |
12/01/2019 |
5300 |
3000 |
| 0230 |
12/17/2019 |
1300 |
200 |
| 0253 |
12/20/2019 |
3100 |
1500 |
Example of COUNT() Function
SELECT COUNT (ORD_ID)
FROM ORDERS;
Result Look Like
Example of AVG() Function
SELECT AVG (ADVANCE_AMOUNT)
FROM ORDERS;
Result Look Like
| ADVANCE_AMOUNT |
| 1216.66666 |
Example of SUM() Function
SELECT SUM (ORD_AMOUNT)
FROM ORDERS;
Result Look Like