AllAccepted answers
Robert Cemper · Sep 24

From Class Docs:
• classmethod ExportAllClassesIndividual(dirname As %String = "", qspec As %String = "", ByRef errorlog As %String, Charset As %String = "", Package As %String = "*", SubDir As %Boolean = 0) as %Status

Export all the classes as individual XML files to a directory.

This method loops through all the classes, exporting each one as an individual XML file named after the classname to the directory dirname. If you specify a Package, then it exports only this package. If SubDir is true,, the method exports sub-packages as subdirectories.

Now the directory is your list of classes and equal sizes of files 
might most likely mean identical content. Or you do a text compare

Robert Cemper · Sep 24

You are right. $system.OBJ.Export~whatever is oriented to the Namespace

BUT:
There still seems to be no limitation to map a specific database file
to more than 1 namespace. e.g. USER and MERGER (here Read Only)
Then $system.OBJ.Export~whatever takes what it finds in MERGER.
It's quite a dirty approach and only meant for READING the code, therefore, ReadOnly

In any case, it's safer just to copy the (most likely static) DB of interest
and use it in MERGER
 

Robert Cemper · Sep 2

When I started in business, quite back in the last century, certifications were not common practice.
Only certificates from European Universities, with just a few from IBM were accepted.
Recruiters were impressed, but managers were more sceptical about.

Having collected a bunch of certificates, this was some disappointment to me.

My later boss explained it to me:

The certificates show that you are strong in learning and delivering tests
Here, we have to provide fast and stable code. This counts.
I had a Dr. Math. from the University that, after 4 weeks of training, was
   not able to write 17 correct running lines of assembly language.
What worth does its certificate have for me ?

This was 53 years ago, and I decided on less noise on paper and more work success

Times are different today

Robert Cemper · Aug 16

I'm fully in Sync with @Dmitry Maslennikov 
Uniqueness is the TOP priority. 
Though you can switch it off for rare cases by the class parameter  MANAGEDEXTENT.

Concerning access speed, naming is not really relevant.
Top level of global storage is a sorted hierarchical directory structure that points to the globals.
So, on average, any global has - with actual storage speed -  the same access time.
And global directory is mostly permanently cached in Global buffers.

BTW: You can list this directory using ^$GLOBAL()

set dir="^$GLOBAL("""")"
for  write dir,! set dir=$QUERY(@dir) quit:dir=""
Robert Cemper · Aug 15

Just as you, I start my CSP also from good old Studio

the EXIT button is inside <bod>y<form> ....<button>..   </form></body>
in upload
 

<!-- Copyright (c) 2001 InterSystems Inc. ALL RIGHTS RESERVED. -->
<csp:class description="Demo of how to upload a file from the browser.">
<html>

<head>
</head>

<body bgcolor="#CCCCFF">

<!-- display standard sample template using a custom tag -->
<isc:SAMPLE title="Upload a file Sample">
This sample uses an '&lt;input type=file&gt;' element in a form to upload a file
from the web browser to CSP. Pick a file and hit the submit button to try it.
</isc:SAMPLE>

<!-- HTML Form to submit the file. You must specify the enctype="multipart/form-data" -->
<!-- for this to work -->
<form enctype="multipart/form-data" method="post" action="upload.csp">
	Enter a file to upload here: <input type=file size=30 name=FileStream>
	<p>
	<ul><input type="submit" value="Upload file"></ul>
	<p>
	<button onclick="window.close()" style="width: 100px; height: 40px; font-size: 18px;"> Exit </button>
</form>

<!-- As form is submitted to this page look to see if we have the stream in the %request object -->
<csp:if condition='($data(%request.MimeData("FileStream",1)))'>
	<hr><br>
	Submitted filename: <b>#(..EscapeHTML(%request.MimeData("FileStream",1).FileName))#</b><br>
	Size of file: <b>#(..EscapeHTML(%request.MimeData("FileStream",1).Size))#</b><br>
	Mime Section: <b>#(..EscapeHTML(%request.MimeData("FileStream",1).MimeSection))#</b><br>
	Type of stream: <b>#(..EscapeHTML($classname(%request.MimeData("FileStream",1))))#</b><br>
	Content Type: <b>#(..EscapeHTML(%request.MimeData("FileStream",1).ContentType))#</b><br>
	<br>
	First 200 characters of stream:<br>
	<ul>
	<script language="Cache" runat="server">
		New bytes
		Set bytes=%request.MimeData("FileStream",1).Read(200)
		Set bytes=##class(%CSP.Utils).DecodeData(bytes)
		Write bytes,!
	</script>
	</ul>
</csp:if>

</body>
</html>

while your calling JS script is best located in <head>......</head>

<html>
<head>
<title>Demo for David</title>
<script language="JavaScript" type="text/javascript">
function importExtract()
{
	var url='upload.csp' ;
	var options = 'popup,status=yes,scrollbars=yes,resizable=yes,width=750,height=250' ;
	newwindow=window.open(url,'UPLOAD',options);
    newwindow.focus();
	alert('back');
	}
</script>
</head>
<body>
<h3>Demo for David</h3>
<Input type="button" value="Import Client Consultation Extract"
         onclick="importExtract();"/>
</body>
</html>