select max codeigniter

Question

Im trying to get an max value with codeigniter from an table but it isnt working. This is the error i get:

Severity: 4096

Message: Object of class CI_DB_mysql_result could not be converted to string

Filename: database/DB_active_rec.php

Line Number: 427

This is my function:

public function getPeriodeNummer($bedrijf_id) {
    $this->db->select_max('id');
    $this->db->where('bedrijf_id', $bedrijf_id);
    $result = $this->db->get('rapporten');

    $this->db->select('periode_nummer');
    $this->db->where('rapporten_id', $result);
    $query = $this->db->get('statistieken_onderhoud');

    $data = $query + 1;

    return $data;
}

What im trying to do is as followed:

Select the highest id where bedrijf_id = $bedrijf_id from rapporten.
Select the periode_nummer from statistieken_onderhoud where rapporten_id = the highest id i got from step 1.
Add 1 to the periode_nummer i got from step 2 and return that number.

Thanks in forward for your help!

stealthyninja · Accepted Answer · 2014-10-31T15:21:16.933

18

Try

public function getPeriodeNummer($bedrijf_id) {
    $this->db->select_max('id');
    $this->db->where('bedrijf_id', $bedrijf_id);
    $res1 = $this->db->get('rapporten');

    if ($res1->num_rows() > 0)
    {
        $res2 = $res1->result_array();
        $result = $res2[0]['id'];

        $this->db->select('periode_nummer');
        $this->db->where('rapporten_id', $result);
        $query = $this->db->get('statistieken_onderhoud');

        if ($query->num_rows() > 0)
        {
            $row = $query->result_array();
            $data['query'] = 1 + $row[0]['periode_nummer'];
        }

        return $data['query'];
    }

    return NULL;
}

edited Oct 31 '14 at 15:21

answered Jan 18 '12 at 13:38

stealthyninja

10,343
11
51
59

1

And this works perfectly, now the challenge to see what its doing to learn from it. But it works, thanks alot!. – Augus Jan 18 '12 at 14:25
@Angus -- Please see CodeIgniter's user guide entries for [example queries](http://codeigniter.com/user_guide/database/examples.html) and [Active Record](http://codeigniter.com/user_guide/database/active_record.html) for further explanation and reference for the functions I used. – stealthyninja Jan 18 '12 at 14:39

score 2 · Answer 2 · answered Aug 10 '17 at 05:11

2

Try this:

    $this->db->select_max('display_sequence');
    $this->db->from('acl_menu');
    $query = $this->db->get();
    $r=$query->result();

Display Sequence is your column name & acl_menu is your table name.

answered Aug 10 '17 at 05:11

Santosh Pandey

131
3

score 1 · Answer 3 · edited Oct 04 '19 at 06:58

1

$this->db->select_max('id', 'max_id');
$query = $this->db->get('video_processing');

return $query->row();

try the above:

edited Oct 04 '19 at 06:58

Kostas Charitidis

2,991
1
12
23

answered Oct 04 '19 at 06:05

Maicol Romero

9
1
2

score 1 · Answer 4 · answered Jan 18 '12 at 13:50

You can't use an object as a string. Use this:

public function getPeriodeNummer($bedrijf_id) {
    $this->db->select_max('id');
    $this->db->where('bedrijf_id', $bedrijf_id);
    $result = $this->db->get('rapporten');

    $this->db->select('periode_nummer');
    $this->db->where('rapporten_id', $result);
    $query = $this->db->get('statistieken_onderhoud');
    // fetch first row in object
    $result = $query->row();
    $data = $result + 1;

    return $data;
}

score 0 · Answer 5 · answered Aug 02 '21 at 08:38

0

Shortest:

$this->db->select_max('id', 'max_id')->get('video_processing')->row();

answered Aug 02 '21 at 08:38

pgrono

740
7
5

score 0 · Answer 6 · answered Jan 18 '12 at 13:22

0

I think the $query variable is holding a mysql result resource and it cannot be used as a String or in this case an Integer.

You could try this way:

$data = mysql_result($query,0) + 1;

answered Jan 18 '12 at 13:22

gustyaquino

767
1
7
28

Tried it, but didnt work, I also tried to make `$result` and mysql_result but that gave me this error `Message: mysql_result() expects parameter 1 to be resource, object given` – Augus Jan 18 '12 at 13:28

select max codeigniter

6 Answers6