php - multiple tables in 1 query -

i have 2 tables in database:

bogie table:

+----------+----------+---------+----------+ | bogie_id | train_id | axle_nr | bogie_nr | +----------+----------+---------+----------+ |        1 |        1 |       1 |        1 | |        2 |        1 |       2 |        1 | |        3 |        1 |       3 |        2 | |        4 |        1 |       4 |        2 | +----------+----------+---------+----------+ 

axle table:

+---------+----------+------+----------+ | axle_id | train_id | axle | distance | +---------+----------+------+----------+ |       1 |        1 |    1 |     2500 | |       2 |        1 |    2 |     5000 | |       3 |        1 |    3 |     2500 | +---------+----------+------+----------+ 

now, want show axles bogie table (4) , distances axle table (3)

i made query (don't mind names):

function hopethisworks(){         $sql = "select * axle train_id = :train_id";         $sth = $this->pdo->prepare($sql);         $sth->bindparam(':train_id', $_get['train_id'], pdo::param_int);         $sth->execute();         $res['axle'] = $sth->fetch(pdo::fetch_assoc);           $sql = "select * bogie train_id = :train_id";         $sth = $this->pdo->prepare($sql);         $sth->bindparam(':train_id', $_get['train_id'], pdo::param_int);         $sth->execute();         $res['bogie'] = $sth->fetch(pdo::fetch_assoc);           return $res;     } 

now, when enter this:

$testingggg = $database->hopethisworks(); echo $testingggg['bogie']['axle_nr']; 

i result: "1"

wich becuase first axle_nr in bogie table 1.

however, wana show 4 instead of 1. make loop:

 <?php      $testingggg = $database->hopethisworks();       foreach($testingggg $testingggg){          echo $testingggg['bogie']['axle_nr'];      }   ?> 

i expect result be: 1 2 3 4 instead of that, get:

notice: undefined index: bogie in...

how remove error, , show numbers 1, 2, 3, 4?

edit:

the join query had:

function axleees() {         $sql = "select ti.axle_nr, ti.train_id, ti.bogie_nr, uti.axle_id, uti.train_id, uti.axle, uti.distance                 bogie ti                 join axle uti                 on ti.train_id = uti.train_id                 ti.train_id = :train_id";         $sth = $this->pdo->prepare($sql);         $sth->bindparam(":train_id", $_get["train_id"], pdo::param_int);         $sth->execute();         return $sth->fetchall();     } 

what you're getting here not want do. when you're executing hopethisworks() you're getting array first row of bogie , first row of axle (or second or nth, depending on how mysql orders it)

res['bogie']['bogie_id']=1 res['bogie']['train_id']=1 res['bogie']['axel_nr']=1 res['bogie']['bogie_nr']=1  res['axle']['axle_id'] = 1 res['axle']['train_id'] = 1 res['axle']['axle'] = 1 res['axle']['distance'] = 2500 

that has 2 rows , 4 elements in each. so, when call res['bogie']['axle_nr'] first time works, because reading first row (res['bogie']), second time reading second row (res['axle']) , crashes because you're asking index not defined there.

for want do, guess reading results query should better use join , execute loop this

$i = 0; $aux = $sth->fetch(pdo::fetch_assoc); while ($aux){     $res[i]=$aux; }