gw1500se

It is not clear to me what you are asking since "empty" returns a boolean value. Is the objective to return the first $postal* that is not empty?

Did you look at the resulting HTML source to see if it looks like you expect?

It may not necessarily be in error_log. There may be several different error logs depending on your configuration. Check all error logs.

500 is an internal server error. What does your httpd log say?

Sorry, I didn't realize that was what you wanted to do. Someone has already done that for you on github.

Check out the json_encode documentation and the JSON_PRETTY_PRINT option.

Yes, the mysql extensions have been deprecated for decades. You should have switched to PDO years ago. Now you have no choice.

Did you check your mail server logs and/or httpd logs?

What did you try and what error did you get or unexpected output?

Once you have the redirect in place, does it matter?

Yes. No.

Use .htaccess to redirect references to the old link to the new one.

Post your code. Be sure to use the code icon (<>) on the menu and specify PHP.

I forgot to mention, not HTML is needed since no browser is involved. Simply write the script as if it were any other scripting language (bsh, Python, perl, etc.).

Eliminate the meta refresh. When you create a cronjob you tell it how often to run the script. This tutorial tells you how to set up cron.

Not directly but writing your own is pretty simple in both PHP and Javascript.

This is not really a PHP question. You need to create a .htaccess file with redirect. You can see how here.

You could start by posting the offending code and the full error message. When posting code be sure to use the code icon (<>) in the menu and specify PHP.

This is not really a PHP issue. I suggest you ask this on the appropriate *NIX forum.

One additional note. You need to check for 11, 12 and 13 since they are not 11st, 12nd or 13rd. Teens are all 'th'.

Where do you check for 3 and append 'rd'? I can only see 'st', 'nd' and 'th'.

What have you tried? Post your code and be sure to use the code icon (<>) on the menu and specify PHP. List any error messages and/or what you get instead of what you expect.

If that is the case, it sounds like your database schema needs to be rethought.

One way is to translate all <> characters to &lt; and &gt; respectively. You may need to wrap it in <pre>...</pre> tags to format it.

Not sure what you are asking. This is all done on the client side so JavaScript can control what is displayed. Calling a PHP function with Ajax does not change anything on that page unless the JavaScript makes the change. Keep in mind that PHP is server side only and is stateless. JavaScript is client side and can control the current page completely. Thus a different JavaScript/Ajax function will not effect this function.