taking the latest content from a dynamic array - php

Question

A small background of myself is that I'm fairly new to php. I work as an IT assistant and have been asked to edit one of the pages our designers use for samples. I cannot point you to the page as it is an internally hosted page.
I'm honestly not even sure if the question is asked correctly but please bear with me.
The page has a 'request completion date' field within a table that outputs 6 dates in a list, the designers only want it to output the latest date from that list instead of all 6, usually these will be empty so it's no use having them printed.
The code to put them is as follows;
if ($database_data['request_confirmed_comp_date'] > "0")
{ $request_confirmed_completion_date = date("d/m/Y", $database_data['request_confirmed_comp_date']); }
else
{ $request_confirmed_completion_date = " -"; }
if $database_data['request_confirmed_comp_date2'] > "0")
{
$request_confirmed_completion_date2 = date("d/m/Y", $database_data['request_confirmed_comp_date2']);
}
else
{
$request_confirmed_completion_date2 = " -";
}
if ($database_data['request_confirmed_comp_date3'] > "0")
{
$request_confirmed_completion_date3 = date("d/m/Y", $database_data['request_confirmed_comp_date3']);
}
else
{
$request_confirmed_completion_date3 = " -";
}
if ($database_data['request_confirmed_comp_date4'] > "0")
{
$request_confirmed_completion_date4 = date("d/m/Y", $database_data['request_confirmed_comp_date4']);
}
else
{
$request_confirmed_completion_date4 = " -";
}
if ($database_data['request_confirmed_comp_date5'] > "0")
{
$request_confirmed_completion_date5 = date("d/m/Y", $database_data['request_confirmed_comp_date5']);
}
else
{
$request_confirmed_completion_date5 = " -";
}
if ($database_data['request_confirmed_comp_date6'] > "0")
{
$request_confirmed_completion_date6 = date("d/m/Y", $database_data['request_confirmed_comp_date6']);
}
else
{
$request_confirmed_completion_date6 = " -";
}
if ($database_data['request_date_required'] > "0")
{
$request_date_required = date("d/m/Y", $database_data['request_date_required']);
}
else
{
$request_date_required = "-";
}
if ($database_data['request_date'] > "0")
{
$request_date = date("d/m/Y", $database_data['request_date']);
}
else
{
$request_date = "-";
}
It is then called into play using;
echo '<td><b>1.</b>'.$request_confirmed_completion_date.'<br /><b>2.</b>'.$request_confirmed_completion_date2.'<br /><b>3.</b>'.$request_confirmed_completion_date3.'<br /><b>4.</b>'.$request_confirmed_completion_date4.'<br /><b>5.</b>'.$request_confirmed_completion_date5.'<br /><b>6.</b>'.$request_confirmed_completion_date6.'</td>';
Now I may not have much php knowledge, but I know that's a horribly long way of doing that. Is there anyway that I could pull the latest date out of an array, created by the the first block of code, and then output them into the table.
Thanks for any help or advice, even if you could just point me in the right direction as to what loop to use would be helpful.
Edit: I've uploaded the full file online here, hopefully that will clear up some confusion.

Answer 1

You want to use the php function asort. Since all of your values look to be numeric, you should be able to do a standard sort and pull off the last item with array_pop.
It might look something like this:
asort($database_data);
$latest = array_pop($database_data);
echo date('m/d/Y', $latest);

Answer 2

Create an array with the variable names, like if the variables are $A, $B and $C, then
$vars = array("A","B","C");
foreach($vars as $var_name){
if($database_data[$var_name] > "0")
$$var_name = $database_data[$var_name];
else
$$var_name = "-";
}
Note: A, B and C are dummy variable names, as the variable names are too long in your code :-)

Answer 3

Firstly there is a problem with your if conditions, you can't say $x > "0" because with using double-quotes you are using 0 as a string. You should use integer $x > 0.
Now here my answer :
I couldn't understand your system very well, so i'm assuming always there will be 6 dates.
for($q = 0;$q < 6; $q++)
{
if($database_data[...][$q] > 0)
$dates[] = date("d/m/Y", $database_data['...'][$q]);
else
$dates[] = " - ";
}
As you see, you have to fetch your database datas as an array $database_data['...'][].

Answer 4

If you can tweak the original SQL statement, which probably looks something like this:
select request_confirmed_comp_date, request_confirmed_comp_date2, request_confirmed_comp_date3, request_confirmed_comp_date4, request_confirmed_comp_date5, request_confirmed_comp_date6
from sometablename
where somefield='something'
You can tweak it to use shorter (and consistent) field names
select request_confirmed_comp_date as date1, request_confirmed_comp_date2 as date2, request_confirmed_comp_date3 as date3, request_confirmed_comp_date4 as date4, request_confirmed_comp_date5 as date5, request_confirmed_comp_date6 as date6
from sometablename
where somefield='something'
And then in PHP use an array to iterate over the field names like so:
<?php
$lastCompletionDate=""; //start by assuming there was no completion date
for($i=1;$i<=6;$i++) { //check to see if any field is after the last known completion date
if ($database_data['date'.$i] && (date("d/m/Y", $database_data['date'.$i]) > $lastCompletionDate)) {
//if so, store the new date
$lastCompletionDate=date("d/m/Y", $database_data['date'.$i]);
}
}
if($lastCompletionDate) {
echo "The last completion date was $lastCompletionDate\n";
}else {
echo "There was no completion date.\n";
}
?>

Answer 5

An alternative solution would be to use the SQL engine's own internal functions to find the highest date like so:
select greatest(request_confirmed_comp_date,
request_confirmed_comp_date2,
request_confirmed_comp_date3,
request_confirmed_comp_date4,
request_confirmed_comp_date5,
request_confirmed_comp_date6) as greatestcompdate
from sometablename etc...
and then refer to that in PHP like
<?php
if($database_data['greatestcompdate']) {
echo "There was a greatest completion date and it was $database_data[greatestcompdate]";
}
?>