Hex converter giving invalid results

[kartik1000]

Describe the bug

The hexadecimal converter 'HEX' in the insert field is giving invalid results. Suppose if I enter 70 as my int value it should give answer as '46' in HEX but it is giving answer as '3730'.
The 'OCT' converter for the same is working correct as I verified.

To Reproduce

1. Add int type column in any table.
2. Go to insert section.
3. Select the function 'HEX' in that 'int' column.
4. Enter some int value and observe the result in the added column

Expected behaviour

The 'HEX' function should give out the corrected value.

Screenshots

This value '3730' was received from type conversion of int '70' to hex

Server configuration

Operating system: macOS Server(5.7.1 )
Web server: Apache/2.4.37 (Unix) OpenSSL/1.0.2q PHP/7.3.0 mod_perl/2.0.8-dev Perl/v5.16.3
Database version: Localhost via UNIX socket
PHP version: 7.3.0
phpMyAdmin version: 4.8.4

Client configuration

Browser: Safari (12.0.3)
Operating system: macOS Mojave (version 10.14.2)

Additional context

Add any other context about the problem here.

[kartik1000]

@williamdes, this was the one

[apoorvkhare07]

@williamdes I was looking into this issue and found that the issue is not with PMA code, rather this is a issue with mysql itself.

mysql give different output of HEX() when passed string('70') or int(70) whereas OCT() give same output for int and string.

[kartik1000]

Nice lead @apoorvkhare07👍. But shouldn't the input field take it as an int since my column type is int

[thesmallstar]

@williamdes, I wanted to work on this.
The real issue is we cannot store a Hexadecimal number in an integer format if we convert an integer to hex it is quite possible it would have Alphabets that cannot be stored in an int.

But if we treat the integer as String we have a very special benefit.

Consider the number 4:

If we treat this as '4' instead it would be converted to hex in the following format:
HEX(ASCII(4)) = HEX(52) = 34

Similarly, the 'answer' for "44" is 3434.

So what is the benefit:
We can convert any number in string format from 0-9 in Hexa and still not use an alphabet i.e A, B etc
Hexa decimal value will vary from 30-39

In this way, we can treat an int as a string and then convert it back to int, doing the required type castings or conversions.

I am sharing the link for trial if needed:
http://string-functions.com/string-hex.aspx
https://codebeautify.org/hex-string-converter

How to solve this problem?
This is not a problem, I feel this was done intentionally.
but we need to tell the user what is happening/ what he is doing.
So I wanted to add a quick note and let the user know the result of his action.
Should I proceed?

[williamdes]

Should I proceed?

@thesmallstar Yes, I think the best Idea is that I can see your proposal to better understand it

What bout #15147 ?

[thesmallstar]

@williamdes , have a look at this

When we implement the PR, unexpected behaviour is shown, since now Alphabets are also returned by the function. I don't think it is needed, only a note for the user will do regarding what he is trying to do.

On which branch do I need to proceed?

[williamdes]

I understand, thank you for the example
Use QA_5_0 for the fix

[kartik1000]

@thesmallstar I agree with you. I opened the issue because I felt I was not able to understand the behavior of the function and there should be a quick note regarding what you mentioned.