PREG_REPLACE in MySQL and PREG_REPLACE_EVAL

Question

I'm using this UDF for the PREG_REPLACE function in MySQL and everything seems to be working fine so far. However, my goal now is to find and encode entities inside pre tags in a column. So ultimately I'd like to get this:

<pre>
    <strong>Hello World!</strong>
</pre>

To look like this:

<pre>
    &lt;strong&gt;Hello World!&lt;/strong&gt;
</pre>

I'm using the PREG_REPLACE function to find the contents inside the pre tags like this:

SELECT PREG_REPLACE('/<pre>(.*?)<\\/pre>/sm', '\\1', '<pre><strong>Hello World</strong></pre>');

Now I'd like to replace \\1 with something that would say "replace with ENCODE_ENTITIES('\\1'). Obviously it could be any other function, like UPPER for example, but UPPER('\\1') doesn't give much. I kind of like the idea of PREG_REPLACE_EVAL in PHP's implementation of preg_replace which allows something like this:

preg_replace("/(<\/?)(\w+)([^>]*>)/e", 
    "'\\1'.strtoupper('\\2').'\\3'", 
    $html_body);

Any ideas on how to implement something similar in MySQL? Or maybe I'm heading the wrong way? Thanks!

Answer 1

Unless you want to modify the source code for the UDF to add that feature, there's no way to do that in MySQL. I suggest you pick your favorite programming language and write a program to make the update for you, or perhaps ensure that this modification is performed before the data hits the database.