POWER FAQS

 1. What does the POWER function do in Oracle?

The POWER function is used to calculate the result of raising a base number to the exponent (i.e., it computes the power of a number). It returns the base raised to the power of the exponent.

Syntax:

POWER(base, exponent)

 

2. What is the syntax for the POWER function?

The syntax for using the POWER function is:

POWER(base, exponent)

• base: The base number to be raised to a power.
• exponent: The exponent to which the base will be raised.

 

3. What happens if the exponent is negative?

When the exponent is negative, the POWER function will return the reciprocal of the base raised to the absolute value of the exponent.

For example:

SELECT POWER(2, -3) FROM dual;  -- Returns 0.125 because 2 raised to the power of -3 is 1 / (2^3)

 

4. What happens if I pass a zero as the base?

If the base is zero and the exponent is positive, the result will be 0. However, if the exponent is zero, the result will be 1.

For example:

SELECT POWER(0, 2) FROM dual;   -- Returns 0 because 0 raised to any positive power is 0

SELECT POWER(0, 0) FROM dual;   -- Returns 1 because 0 raised to the power of 0 is defined as 1

 

5. What happens if I pass a zero as the exponent?

Any non-zero number raised to the zero power will return 1. This is because any number to the power of 0 is 1 (except for 0 itself).

For example:

SELECT POWER(5, 0) FROM dual;  -- Returns 1

 

6. Can the POWER function handle fractional exponents (e.g., square roots)?

Yes, the POWER function can be used to calculate fractional powers. For example, the square root of a number can be calculated using an exponent of 0.5 (which is equivalent to raising the base to the power of 1/2).

Example:

SELECT POWER(9, 0.5) FROM dual;  -- Returns 3, which is the square root of 9

 

7. What happens if I pass a negative number as the base?

The base can be negative, but the exponent must be an integer when using negative numbers as the base (for real number results). Otherwise, a complex result will be generated.

For example:

SELECT POWER(-2, 3) FROM dual;  -- Returns -8 because (-2)^3 = -8

However, fractional exponents with a negative base result in complex numbers.

 

8. What data types can be used with the POWER function?

The POWER function can be used with any numeric data type such as:

• NUMBER
• FLOAT
• DECIMAL
• INTEGER
• DOUBLE

It cannot be used with non-numeric data types (e.g., strings or dates).

 

9. Can I use the POWER function in a WHERE clause?

Yes, you can use the POWER function in a WHERE clause to filter rows based on the result of an exponentiation calculation.

Example:

SELECT product_name, price

FROM products

WHERE POWER(price, 2) > 100;

This query returns products whose squared price is greater than 100.

 

10. Does the POWER function handle NULL values?

Yes, if you pass a NULL value to the POWER function, it will return NULL as the result.

For example:

SELECT POWER(NULL, 2) FROM dual;  -- Returns NULL

 

11. How do I use the POWER function with other mathematical functions?

You can combine the POWER function with other mathematical functions, such as ROUND, ABS, CEIL, etc., to further process the result of the power calculation.

Example:

SELECT ROUND(POWER(price, 2), 2) AS price_squared_rounded

FROM products;

 

12. What is the return type of the POWER function?

The return type of the POWER function is NUMBER, which represents the result of raising the base to the exponent.