MYSQL: Validate Input with Regular Expressions REGEX - mysql

Question

i have one question with regard to MYSQL. I want to create a function that is able to check whether an Input is given in a specific format.
The output should be in the following shape:
***x x (a) n (n) (n) (n)
with :
x = letters and numbers
n = numbers
a = letters
brackets = optional Values***
So my Solution until now is this (User 'Nick' helped me):
CREATE FUNCTION validate_number(testnumber VARCHAR(7))
RETURNS INT
DETERMINISTIC
RETURN testnumber REGEXP '^[[:alnum:]]{2}[[:alpha:]]?[[:digit:]]{1,4}$';
And this approach works for most cases.
But when i enter a value that exceeds the possible amount of elements (max elements = 7) i get no result.
example:
validate_number('00A00002345')
=> no result.
Do you guys have an idea what the problem is?
Thank you very much in advance.

Answer 1

you are actually pointing out the solution of the problem :)
just change VARCHAR(7) to something bigger VARCHAR(2000)

Answer 2

When I run your function, I get the error:
select validate_number('00A00002345')
Data too long for column 'testnumber' at row 1
You can add a length to the varchar.
CREATE FUNCTION validate_number (
in_testnumber VARCHAR(32000)
)
Or, use text:
CREATE FUNCTION validate_number (
in_testnumber text
)
RETURNS INT
DETERMINISTIC
BEGIN
RETURN (in_testnumber REGEXP '^[[:alnum:]]{2}[[:alpha:]]?[[:digit:]]{1,4}$');
END;