According to RFC 4288 &quot;Media Type Specifications and Registration Procedures&quot;, type (eg. &quot;application&quot;) and subtype (eg &quot;vnd...&quot;) both [can be max 127 characters][1]. So including the slash, the maximum length is 255.

**Edit:** Meanwhile, that document has been obsoleted by [RFC 6838][2], which does not alter the maximum size but adds a remark:

&gt; Also note that while this syntax allows names of up to 127
&gt; characters, implementation limits may make such long names 
&gt; problematic. For this reason, `&lt;type-name&gt;` and `&lt;subtype-name&gt;` SHOULD 
&gt; be limited to 64 characters.



  [1]: https://datatracker.ietf.org/doc/html/rfc4288#section-4.2
  [2]: https://datatracker.ietf.org/doc/html/rfc6838#section-4.2

Is there any built-in function that allows me to deep copy an `NSMutableArray`?

I looked around, some people say `[aMutableArray copyWithZone:nil]` works as deep copy. But I tried and it seems to be a shallow copy.

Right now I am manually doing the copy with a `for` loop:

    //deep copy a 9*9 mutable array to a passed-in reference array

    -deepMuCopy : (NSMutableArray*) array 
    	toNewArray : (NSMutableArray*) arrayNew {
    
    	[arrayNew removeAllObjects];//ensure it&#39;s clean
    
    	for (int y = 0; y&lt;9; y++) {
    		[arrayNew addObject:[NSMutableArray new]];
    		for (int x = 0; x&lt;9; x++) {
    			[[arrayNew objectAtIndex:y] addObject:[NSMutableArray new]];
    				
    			NSMutableArray *aDomain = [[array objectAtIndex:y] objectAtIndex:x];
    			for (int i = 0; i&lt;[aDomain count]; i++) {
    				
    				//copy object by object
    				NSNumber* n = [NSNumber numberWithInt:[[aDomain objectAtIndex:i] intValue]];
    				[[[arrayNew objectAtIndex:y] objectAtIndex:x] addObject:n];
    			}
    		}
    	}
    }

but I&#39;d like a cleaner, more succinct solution.

Deep copying an NSArray

Are there any alternatives to the code below:

    startFromLine = 141978 # or whatever line I need to jump to

    urlsfile = open(filename, &quot;rb&quot;, 0)

    linesCounter = 1

    for line in urlsfile:
        if linesCounter &gt; startFromLine:
            DoSomethingWithThisLine(line)
        
        linesCounter += 1
        
If I&#39;m processing a huge text file `(~15MB)` with lines of unknown but different length, and need to jump to a particular line which number I know in advance? I feel bad by processing them one by one when I know I could ignore at least first half of the file. Looking for more elegant solution if there is any.

How to jump to a particular line in a huge text file?

What are people using as the length of a MIMEType field in their databases? The longest one we&#39;ve seen so far is 72 bytes:

    application/vnd.openxmlformats-officedocument.wordprocessingml.document

but I&#39;m just waiting for a longer one. We&#39;re using 250 now, but has anyone seen a longer MIMEType than that?

Edit: From the accepted answer, 127 for type and sub-type each, so that&#39;s 254 max, plus the &#39;/&#39; is a limit of 255 for the combined value.

Maximum MIMEType Length when storing type in DB

What are people using as the length of a MIMEType field in their databases? The longest one we've seen so far is 72 bytes:
<pre><code class="hljs language-bash">application/vnd.openxmlformats-officedocument.wordprocessingml.document
</code></pre>
but I'm just waiting for a longer one. We're using 250 now, but has anyone seen a longer MIMEType than that?
Edit: From the accepted answer, 127 for type and sub-type each, so that's 254 max, plus the '/' is a limit of 255 for the combined value.

Ok, dumb question I know but I see the nebulous comment &#39;a large database&#39; as well as small and medium and I wonder just what that means. Can someone define what a small, medium and large database is for us SQL neophytes?

Just what is &#39;A big database&#39;?

I thought that I could use SimpleDB to take care of the most challenging area of my application (as far as scaling goes) - twitter-like comments, but with location on top - till the point when I sat down to actually start implementing it with SDB.

First thing, SDB has a 1000 bytes limitation per attribute value, which is not enough even for comments (probably need to break down longer values into multiple attributes). 

Then, maximum domain size is 10GB. The promise was that you could scale up without worrying about database sharding etc., since SDB will not degrade with increasing loads of data. But if I understand correctly, with domains I would have exactly the same problem as with sharding, ie. at some point need to implement data records&#39; distribution and queries across domains on application level.

Even for the simplest objects that I have in the whole application, ie. atomic user ratings, SDB is not an option, because it cannot calculate an average within the query (everything is string based). So to calculate average user rating for an object, I would have to load all records - 250 at a time - and calculate it on application level.

Am I missing something about SDB? Is 10GB really that much of a database to get over all SDB limitations? I was honestly enthusiastic about taking advantage of SDB, since I use S3 and EC2 already, but now I simply don&#39;t see a use case.

What&#39;s the point of using Amazon SimpleDB?

Listening to Scott Hanselman&#39;s interview with the Stack Overflow team ([part 1](http://www.hanselminutes.com/default.aspx?showID=152) and [2](http://www.hanselminutes.com/default.aspx?showID=153)), he was adamant that the SQL server and application server should be on separate machines.  Is this just to make sure that if one server is compromised, both systems aren&#39;t accessible?  Do the security concerns outweigh the complexity of two servers (extra cost, dedicated network connection between the two, more maintenance, etc.), especially for a small application, where neither piece is using too much CPU or memory?  Even with two servers, with one server compromised, an attacker could still do serious damage, either by deleting the database, or messing with the application code.  

Why would this be such a big deal if performance isn&#39;t an issue?

Why is it not advisable to have the database and web server on the same machine?

Apart from the google/bigtable scenario, when shouldn&#39;t you use a relational database? Why not, and what should you use? (did you learn &#39;the hard way&#39;?) 


When shouldn&#39;t you use a relational database?

I would like to write a script which copies my current database `sitedb1` to `sitedb2` on the same mysql database instance. I know I can dump the sitedb1 to a sql script:

    mysqldump -u root -p sitedb1 &gt;~/db_name.sql

and then import it to `sitedb2`. 
Is there an easier way, without dumping the first database to a sql file?



MySQL: Cloning a MySQL database on the same MySql instance

OK, I understand what the messages *means*, but I&#39;m really not sure what&#39;s causing it. I&#39;m using Safari and the Web Inspector on Mac OS X, by the way.

I&#39;ve got the following in my document head:

    &lt;script src=&quot;http://local.url/a/js/jquery.js&quot; type=&quot;text/javascript&quot;&gt;&lt;/script&gt;
    &lt;script src=&quot;http://local.url/a/js/jquery.inplace.js&quot; type=&quot;text/javascript&quot;&gt;&lt;/script&gt;

`jquery.js` is handled fine, but the other file causes the warning. It also seems that the javascript in this file never gets executed.

The file is being served via `mod_deflate`, so it is gzip encoded, but so is the other file.

Has anybody got any ideas what&#39;s causing this, or how to resolve it?

Cheers all,
Gaz.


Debug message &quot;Resource interpreted as other but transferred with MIME type application/javascript&quot;

I&#39;m getting a &quot;not well-formed&quot; error in the error console of Firefox 3.0.7 when the JavaScript on my page loads a text file containing an object in JavaScript Object Notation format. If the file contains nothing but the JSON object, it produces the error. If I wrap the object in &amp;lt;document&amp;gt;&amp;lt;/document&amp;gt; tags it does not produce the error. The request succeeds either way, so I could just ignore it, but I don&#39;t want my error log filling up with these messages.

Here is some example code to illustrate the problem. First, the &quot;not well-formed&quot; file called &quot;data.json&quot;:

    { a: 3 }

Now some code to load the file:

    var req = new XMLHttpRequest();
    req.open(&quot;GET&quot;, &quot;data.json&quot;);
    req.send(null);

Which produces the following error in the Firefox error console:

**not well-formed**  
file://path/to/data.json                    Line: 1  
{ a: 3 }  
- ^

If data.json is modified to this:

    &lt;document&gt;{ a: 3 }&lt;/document&gt;

There is no error. I assumed that it is complaining because the plain JSON file is not a well formed XML document, so I tried overriding the MIME type before the &quot;send&quot; call to force it to load as plain text, but that didn&#39;t work.

    var req = new XMLHttpRequest();
    req.open(&quot;GET&quot;, &quot;data.json&quot;);
    req.overrideMimeType(&quot;text/plain&quot;);
    req.send(null);
    // Still produces an error!

I am going to continue with wrapping my JSON data in an XML document to get around whatever validation the XMLHttpRequest is performing, but I&#39;d like to know if there is any way I can force it to just load plain text uncritically and not try to validate it. Alternatively, is there another method of loading data besides XMLHttpRequest that can be used with plain text?

&quot;not well-formed&quot; error in Firefox when loading JSON file with XMLHttpRequest

I am trying to read a image file (.jpeg to be exact), and &#39;echo&#39; it back to the page output, but have is display an image...

my index.php has an image link like this:

    &lt;img src=&#39;test.php?image=1234.jpeg&#39; /&gt;

and my php script does basically this:

1) read 1234.jpeg
2) echo file contents...
3) I have a feeling I need to return the output back with a mime-type, but this is where I get lost

Once I figure this out, I will be removing the file name input all together and replace it with an image id.

If I am unclear, or you need more information, please reply.

Return a PHP page as an image

The closest thing I could find was `System.Net.Mime.MediaTypeNames` but that doesn&#39;t seem to have everything (like json) since it seems to be more focused around email attachments.



Is there an enum for the ContentType property on a HttpWebResponse (&quot;text/plain&quot;, &quot;application/octet-stream&quot; etc.)?

Do I have to specify a MIME type if the uploaded file has no extension?
In other words is there a default general MIME type?

Content Type	Original Author	Original Content on Stackoverflow
Question	Walden Leverich	View Question on Stackoverflow
Solution 1 - Database	ax.	View Answer on Stackoverflow

Maximum MIMEType Length when storing type in DB

Database Problem Overview

Database Solutions

Solution 1 - Database

How to jump to a particular line in a huge text file?

Deep copying an NSArray

Attributions