Retrieve the last array value

PHP
1

Hi ALL,

I’d like to retrieve the last value from an array which is not a tricky thing but I can’t get this to work with a mysql_fetch_array… I’ve tried this :


while ($q_row = mysql_fetch_array($q_inter)) {
	echo end($q_row['date']);
} // end while

with this I get a warning message :


Warning: end() [function.end]: Passed variable is not an array or object in /home/path_to_file/members_interaction.php on line 47

Can someone give a guide here? Thanks in advance!

2

Right.

How many ‘dates’ do you actually need? You’re jumping from 1 to 2, and now 3.

Do you need all 3 but only want to know how to access the last one, or do you just need the 3 one?

:stuck_out_tongue:

3

You just need to edit your LIMIT to obtain the second result only.


SELECT
    date
FROM
    interview_questions
WHERE
    asker_id = 1 
        AND
    answerer_id = 4
ORDER BY
    id DESC
LIMIT 1, 1
4

so you want the second to last one? you can try removing the last array array_pop and then do end()

dunno :stuck_out_tongue: the past 2 weeks i been having a love and hate relationship with arrays lol

5

What I wanted is to select i.e. that last 10 rows (dates) from the DB table and then to pick the last one of those. Maybe it’s not the elegant way but I managed to do it with these lines :


$q_inter = mysql_query("SELECT date FROM interview_questions WHERE asker_id = '".$_SESSION['user_id']."' AND answerer_id = '$contact_to_add' ORDER BY id DESC LIMIT 10");
$nr_of_int = mysql_num_rows($q_inter);
if ($nr_of_int > 0) {
	for ($i=0; $i<$nr_of_int; $i++) {
	$row = mysql_fetch_array($q_inter);
	$var[ ] = $row;
}
	$last_int_date = $var[$nr_of_int-1]['date'];
6

Yes, that would be easier, but I need to select the 2 last rows and then pick the first of those 2… i hope it’s clear enough…

7

That was the 1st thing I tried, but that’s not what I want… It echos all the date values in case of the query :


SELECT date FROM interview_questions WHERE asker_id = '".$_SESSION['user_id']."' AND answerer_id = '$contact_to_add' ORDER BY id DESC LIMIT 2

Anyway, thanks for the tip… :slight_smile:

8

Try this instead:


echo end($q_row);

Is that what you’re after?

9

Wouldn’t it just be easier to order your results in descending order by the primary key and limit it to a single result?

Saves looping through all of the data then.

10

Yeah, that’s really more elegant! However, what happens when I have only 6 rows in the table? Will the query do the job in that case as well?

11

You’re right, it’s not. :stuck_out_tongue:

You need the use LIMIT as I posted earlier.


<?php

$result = mysql_query(
    'SELECT date FROM table ORDER BY id DESC LIMIT 9, 1'
);

$row = mysql_fetch_assoc($result);

echo $row['date'];

?>

:wink:

12

Well, thank you guys! I’ve tried to modify the query, but I couldn’t get what I want…
Please have a look at the script :


$q_inter = mysql_query("SELECT date FROM interview_questions WHERE asker_id = '".$_SESSION['user_id']."' AND answerer_id = '$contact_to_add' ORDER BY id DESC LIMIT 3");
$nr_of_int = mysql_num_rows($q_inter);
for ($i=0; $i<$nr_of_int; $i++) {
    $row = mysql_fetch_array($q_inter);
    $var[ ] = $row;
}
echo "<pre>";
print_r ($var);
echo "</pre>";

with this I get at the browser:


Array
(
    [0] => Array
        (
            [0] => 2010-09-25
            [date] => 2010-09-25
        )

    [1] => Array
        (
            [0] => 2010-09-20
            [date] => 2010-09-20
        )

    [2] => Array
        (
            [0] => 2010-09-18
            [date] => 2010-09-18
        )

)

Can you guys now help me to retrieve/echo/whatever the LAST date whis is in this case 2010-09-18? I appreciate your expertise!