POWER(column, exponent)
Base = คอลัมน์, Exponent = ค่าคงที่
ข้อมูล Employee
+----+--------+--------+
| ID | Name | Salary |
+----+--------+--------+
| 1 | Gaurav | 50000 |
| 2 | Rahul | 20000 |
| 3 | Advik | 25000 |
| 4 | Aarav | 65000 |
| 5 | Ram | 20000 |
| 6 | Mohan | 30000 |
| 7 | Aryan | NULL |
| 8 | Vinay | NULL |
+----+--------+--------+
คำสั่ง: ยกกำลัง 2 ของ ID
mysql> SELECT ID, POWER(ID, 2) FROM Employee;
+----+-------------+
| ID | POWER(ID,2) |
+----+-------------+
| 1 | 1 |
| 2 | 4 |
| 3 | 9 |
| 4 | 16 |
| 5 | 25 |
| 6 | 36 |
| 7 | 49 |
| 8 | 64 |
+----+-------------+
Syntax
POWER(base, exponent)
POW(base, exponent) -- synonym
ประยุกต์ใช้
- คำนวณพื้นที่วงกลม:
PI() * POWER(radius, 2) - Compound interest:
principal * POWER(1 + rate, years) - Distance formula:
SQRT(POWER(x2-x1, 2) + POWER(y2-y1, 2)) - Bit operations:
POWER(2, n)= 2^n
NULL Handling
- Base = NULL → คืน NULL
- Exponent = NULL → คืน NULL
