php - Using for() to update multiple rows in mysql database -

i trying update multiple rows in database. have total number of rows in table counted , bound variable:

$result = '32'

i attempt query each row:

for ($x = 0; $x <= $result; $x++) {     if ($update = $db -> prepare("update substrates set substrate_name = ?, substrate_desc = ?, substrate_base = ?, substrate_tax = ? substrate_id = ?"))     {         $substrate_name = $_post['substrate_name'];         $substrate_desc = $_post['substrate_desc'];         $substrate_base = $_post['substrate_base'];         $substrate_tax  = $_post['substrate_tax'];         $substrate_id   = $x;         $update -> bind_param('sssss', $substrate_name, $substrate_desc, $substrate_base, $substrate_tax, $substrate_id);         if ($update -> execute() == true) {             // success stuff...         }          else {             // error stuff...         }         $update -> close();     } } 

my problem when run script, each row in table filled last row edited. example:

aaa | aaaaa | 1.00 | 6.35 bbb | bbbbb | 2.00 | 6.35 ccc | ccccc | 3.00 | 6.35 

becomes:

ccc | ccccc | 3.00 | 6.35 ccc | ccccc | 3.00 | 6.35 ccc | ccccc | 3.00 | 6.35 

how can fix script update each row individually?

try this:

for ($x = 0; $x <= $result; $x++) {     if ($update = $db -> prepare("update substrates set substrate_name = ?, substrate_desc = ?, substrate_base = ?, substrate_tax = ? substrate_id = ?"))     {         $substrate_name = $_post['substrate_name'][$x];         $substrate_desc = $_post['substrate_desc'][$x];         $substrate_base = $_post['substrate_base'][$x];         $substrate_tax  = $_post['substrate_tax'][$x];         $substrate_id   = $x;         $update -> bind_param('sssss', $substrate_name, $substrate_desc, $substrate_base, $substrate_tax, $substrate_id);         if ($update -> execute() == true) {             // success stuff...         }          else {             // error stuff...         }         $update -> close();     } }