Create a PostgreSQL Function that returns a Fixed String

Create a Simple Function to Return a Constant Value

Write a PostgreSQL function that returns the string "Hello, PostgreSQL!" when called.

Solution:

-- Create a function named greet_message
CREATE FUNCTION greet_message() RETURNS TEXT AS $$
BEGIN
-- Return the constant string 'Hello, PostgreSQL!'
RETURN 'Hello, PostgreSQL!';
END;
-- Specify the language used in the function as PL/pgSQL
$$ LANGUAGE plpgsql;

Explanation:

• Purpose of the Query:
• This function demonstrates how to define a PL/pgSQL function that returns a fixed value.
• It is useful for testing function creation and execution.
• Key Components:
• CREATE FUNCTION greet_message() → Defines a function named greet_message.
• RETURNS TEXT → Specifies that the function returns a TEXT value.
• RETURN 'Hello, PostgreSQL!'; → The function always returns this string.
• Real-World Application:
• This could be used for system messages or notifications in a database application.

For more Practice: Solve these Related Problems:

• Write a PostgreSQL function that returns the number 100 every time it is called.
• Write a PostgreSQL function that always returns the current database name.
• Write a PostgreSQL function that returns a hardcoded JSON object containing a name and age.
• Write a PostgreSQL function that returns the sum of two hardcoded numbers (e.g., 15 and 25) without taking any input.

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