How to Create a PostgreSQL Function to Square a Number
Function to Calculate the Square of a Number
Write a PostgreSQL function that takes an integer as input and returns its square.
Solution:
-- Create a function named square_number that takes an integer as input and returns an integer
CREATE FUNCTION square_number(n INT) RETURNS INT AS $$
BEGIN
-- Return the square of the input number
RETURN n * n;
END;
-- Specify the language used in the function as PL/pgSQL
$$ LANGUAGE plpgsql;
Explanation:
- Purpose of the Query:
 - This function computes the square of a given integer.
 - Key Components:
 - CREATE FUNCTION square_number(n INT) RETURNS INT → Defines a function that accepts an integer and returns an integer.
 - RETURN n * n; → Multiplies n by itself to compute the square.
 - Real-World Application:
 - Useful in mathematical calculations, physics simulations, and financial applications.
 
For more Practice: Solve these Related Problems:
- Write a PostgreSQL function that returns the cube of a given number.
 - Write a PostgreSQL function that calculates the absolute difference between two integers.
 - Write a PostgreSQL function that squares a number only if it is even, otherwise returns -1.
 - Write a PostgreSQL function that returns the square root of a number rounded to two decimal places.
 
Go to:
- Comprehensive Guide to writing PL/pgSQL Functions in PostgreSQL Exercises Home. ↩
 - PostgreSQL Exercises Home ↩
 
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