Overview

The CBRT() function calculates and returns the cube root of a given number. In mathematical terms, for a number x, its cube root y is determined by the equation y³ = x.

Syntax

The syntax for the CBRT() function is as follows:

CBRT(number)

Where:

  • number: This is a required value representing the number for which you want to calculate the cube root. It can be a positive or negative whole number, a decimal, or even an expression that evaluates to a number.

For example, you can use expressions like SELECT CBRT(some_column) from test_table, assuming some_column contains a numeric value.

Return Value:
- It will return NULL if the argument is NULL.
- It will give an error if you input a parameter that is not a numeric type.

Examples

Below are several usage examples of the CBRT() function:

Case #1: Basic Cube Root Calculation

Consider the following example:

  SELECT CBRT(125);

The result of this query will be:

 cbrt 
------
    5

Case #2: Cube Root of a Negative Value

To calculate the cube root of a negative number, use the CBRT() function as shown:

  SELECT CBRT(-125);

The final result is as follows.

 cbrt 
------
   -5

Case #3: Cube Root of Decimal Result

For calculations with decimal numbers, use the CBRT() function as demonstrated below:

SELECT CBRT(32);

The result will be a decimal value, as shown below:

       cbrt        
-------------------
 3.174802103936399

Case #4: Cube Root of Decimal Input

In this scenario, fractional seconds are incorporated into the argument:

SELECT CBRT(0.12815);

The result will be the cube root of the provided decimal value.

    cbrt    
------------
 0.50416523

Case #5: Handling Incorrect Argument

When a non-numeric argument is provided, the CBRT() function works as follows:

SELECT CBRT('abc');

An error will be generated, and the result will not be valid.

invalid input syntax for type double precision: "abc"

Case #6: CBRT Operator (||/(x))

Here’s an example using the CBRT operator (||/(x)) to calculate the cube root of a given number:

SELECT ||/(1728) AS cbrt_operator;

In this example, we calculate the cube root of 1728 using the CBRT operator. The result of this query will be:

   cbrt_operator    
--------------------
 12.000000000000002