[RESOLVED] Order an array

[mattm591]

Hi.

I'm trying to order an array based on information from a database.

My array contains document ids, and I want to look up the years associated with these ids and order the array by year.

How can I do this, the only array ordering function I could find was sort() which I couldn't understand how to use, and I didn't think would do this.

Thanks for any help.

Matt

[Piranha]

Do you get the values in the array from the database? If so it is usually much better and simpler to order in the database.

[mattm591]

I do, the reason I'm using the array is because I don't know what values will be needing to be ordered, their specified by the user who chooses certain documents.

[Piranha]

I still say that you should do it with the database query. You must have the sorting order the user want when you do that query, it is pretty easy there but kind of hard in PHP.

[mattm591]

Ok, well I'll give it a try like that then. Thanks for the advice 🙂

Edit:
I have a problem with that.

Here is the code I have

foreach($array as $a){

$query = mysql_query("select * from authorship
  left join authors on authorship.authorid = authors.authorid
  left join docs on authorship.docid = docs.docid
  left join type on authorship.typeid = type.typeid
  where docs.docid = ".$a.);

$result=mysql_fetch_array($query);

As you see I am using the id from the array to locate the data from the database and doing it for each item in the array, so as it's using the docid I don't see how I could now order that.

[leatherback]

Hi,

I am assuming you get one doc per id. Better probably to do:

// create a comma-delimited list of document id's:
$list = implode(', ', $array);
$sortcolum = ... // whatever the coum is that needs to be sorted by

$query "
select * from authorship
  left join authors on authorship.authorid = authors.authorid
  left join docs on authorship.docid = docs.docid
  left join type on authorship.typeid = type.typeid
  where docs.docid in (".$list.") 
  order by ".$sortcolum." ASC";
  $result = mysql_query($query);
  if($result)
    {
    while($row = mysql_fetch_array($result))
      {
      echo $row[0];
      }
   }

[mattm591]

Ok, well that might work but I don't know for sure because when I use the implode thing (which I still don't totally understand 😛) it only outputs one result from the database.

leatherback, if you look at the code I emailed you earlier, how would I integrate the order by bit into something which would also output for all documents selected like the other code does.

I don't know exactly what the implode function is doing, or how that would let me move through the entire array.

Thanks for the help both of you, one day I might be less retarded at PHP!!!

[leatherback]

Hi Matt,

I just got home about 3 hours ago, did not read your email yet. This post is related to the code you emailed me? I'll have a look later tonight.

J.

[mattm591]

It is for the most part, I'll catch up with you about it tomorrow then. Thanks! Theres no rush though, so don't worry about it this evening if your feeling jet lagged or just can't be bothered! 😉

[leatherback]

No problem. Working on it right now. I see a lot of room for improvement in you rcode. Should have it to you in 20 mins (after which I am off to my sofa, cold beer & crisps for a night-of-nothing)

[mattm591]

I have been trying some more to get this thing to order properly and I can't manage it.

So I have made this simpler piece of code which shows the basic principle of what I want to order.

I made a simple array which contains the ids of two documents.

I then run a query for each of the arrays to retrieve data on that particular document. Although I know it has no real effect because it's only selecting for one document I added an ORDER by year at the end.

The result is then to output the year of that document.

What I want is for the documents to be ordered by year when their outputted but with the code in this form I don't know how.

So can anyone, looking at how the code is dealing with the data, suggest a way to order the document ids in the array by the year data stored in the database.

Thanks,

Matt

<?php

error_reporting(E_ALL);

include('db_connect.php');

$docid[] = "18";

$docid[] = "19";

foreach ($docid as $id) {

$query="SELECT * FROM authorship left join authors on authorship.authorid = authors.authorid left join docs on authorship.docid = docs.docid left join type on authorship.typeid = type.typeid where docs.docid='$id' ORDER BY year";

$result=mysql_query($query);

$data=mysql_fetch_array($result);

}

?>

[Installer]

If I read correctly, something like this should work:

foreach ($docid as $id) { 
    $query = "LONG query ALL on one line"; 
    $result = mysql_query($query); 
    $data[] = mysql_fetch_array($result);
    $date[] = $data['date']; 
} 
array_multisort($date, SORT_DESC, $data);

[mattm591]

Yes!!!!!!

That works perfectly, that's been causing be far too much hassle.

Thank you very much! Great stuff.