Check out example codes for "mysql string length". It will help you in understanding the concepts better.

Code Example 1

-- Relevant for MySQL only

-- syntax
LENGTH(<your-string>)

-- example
LENGTH('CountCharacters') -- OUTPUT: 15
        123456789012345

-- example with query 
SELECT 'CountCharacters',LENGTH('CountCharacters')
FROM DUAL;

-- OUTPUT: CountCharacters, 15

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