length Function in PostgreSQL

In PostgreSQL, the LENGTH function is used to return the number of characters in a string expression. Here's how you can use the LENGTH function with an example:

SELECT LENGTH('Hello World') AS string_length;

In this example, 'Hello World' is a string literal. The LENGTH function is applied to this string, and it returns the length of the string, which is 11 characters.

The output of this query would be:

string_length

-------------

11

This demonstrates how to use the LENGTH function in PostgreSQL to find the length of a string.