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For a long time I am looking for a practical (reusable, clear, updateable,...) solution to the following:

I searched on the Web and came to know that PHP code can be compiled to have performance boost. But how to do it? Can I compile both procedural and object oriented PHP code?

I have a problem in writing a query for MySQL. I have following fields in the DB

So if I wanted to organize a list of websites alphabetically, and there were all of this form: example1.com, test.com, stackoverflow.com, google.com, it would be easy. However, I want to also organize subdomains. Consider the following three domains:

I'm trying to parse a plain text document in PHP but have no idea how to do it correctly. I want to separate each word, assign them an ID and save the result in JSON format.

There are 1 on 1 live chat. Two solutions: 1) I store every message into database and with jQuery's help I check if there is a new message in database every second. Of course I use cache either. If there is, we give that message.

I have a custom 404 page which works fine except for the message I want to display on this page.