SQL Again!

[jmarcv]

Hmmmmm, did I release that to the public domain?
Not to complicate issues, but I thought you might be interested.
REGEXP has an 'or' function (but not an 'and' - bummer -). You can separate each search item with a | (pipe) symbol.

So rather than looping through the array and creating multiple REGEXP you can create it in one shot outside of your array loop like so:

 $strProdNameSearch = " concat(' ',pd.products_name,' ') REGEXP '[^a-zA-Z]+".join('[^a-zA-Z]+|[^a-zA-Z]+',$search_keywords)."[^a-zA-Z]+'  "; 
  

This will enhance the speed on searches with numerous search items.

Also of note, while I took the easy way out:
\b allows you to perform a "whole words only" search using a regular expression in the form of \bword\b.

So, I think

 REGEXP '[^a-zA-Z]+$search_keywords[$i][^a-zA-Z]+' 
  

could also be written as

 REGEXP '\b$search_keywords[$i]\b'
 
$strProdNameSearch = " concat(' ',pd.products_name,' ') REGEXP '\b+".join('\b|\b',$search_keywords)."\b'  ";