So you want to store URLs in MySQL, and the URLs have those annoying %20%27%7C%26%5E%2B%2D%25 symbols? And you want to be able to show your users some kind of human-readable information. You might want to consider using this trick. Take this list of commonly escaped characters as an example:

%20 - space
%27 - '
%7C - |
%26 - &
%5E - ^
%2B - +
%2D - -
%25 - %

So, how about we do some search’n'replace on that?

mysql> SET @url:='%20%27%7C%26%5E%2B%2D%25';
Query OK, 0 rows affected (0.00 sec)

mysql> SELECT @url as original,
    ->        REPLACE(REPLACE(REPLACE(REPLACE(REPLACE(REPLACE(
    ->        REPLACE(REPLACE(REPLACE(REPLACE(REPLACE(REPLACE(
    ->        @test,'%20',' '),
    ->        '%27','\''),
    ->        '%7C','|'),  -- REPLACE() is case sensitive
    ->        '%7c','|'),  -- so we have
    ->        '%26','&'),
    ->        '%5E','^'),
    ->        '%5e','^'),  -- to repeat
    ->        '%2D','-'),
    ->        '%2d','-'),  -- ourselves
    ->        '%2B','+'),
    ->        '%2b','+'),  -- sometimes
    ->        '%25','%') as replaced;
+--------------------------+----------+
| original                 | replaced |
+--------------------------+----------+
| %20%27%7C%26%5E%2B%2D%25 |  '|&^+-% |
+--------------------------+----------+
1 row in set (0.01 sec)

mysql>

We can easily turn this into a function: (more…)