having trouble updating value serialized array in MYSQL - php

Question

Here what I does
- extract my serialize array from databse
- deserialize it
- change the value
- after changing I serialize it
- then write it back to MYSQL database table.
But Im having trouble writing it back to MYSQL database table
$myarray = Array
(
[dogname] => Array
(
[0] => white
[1] => zeon
[2] => imao
)
[visit] => Array
(
[0] => once
[1] => twice
[2] => twice
)
}
I save it database with this way into my table serialize($myarray)
now I extract it and unserialize
$unserializearray = unserialize($myserialarray);
then search for array value to change and back to table
$keys = array_keys($unserializearray['dogname'], 'imao', true);
foreach($keys as $key)
{
// find dogname imao and change its visit to once
$unserializearray['visit'][$key] = "once";
$update = serialize($unserializearray);
//save the update
mysql_query("UPDATE dogdetails SET checkup = '$update'
WHERE dogid = '1'");
}
but it dont save right into mysql do I miss something in code?

Answer 1

First of all this can't work, if something in your array has a single quote in it, so you need to do
$update=mysql_real_escap_string(serialize($unserializearray),$dbhandle);
or friends.
More importantly, your database design seem heavily flawed to me: As has been said many, many times here, you should not store more than one value in a field, if you want to access them seperately. In your case, you store three dogs with their vists, but you want to access them seperately - this is what your code does.

Answer 2

As Eugen said, there are many things wrong with your code.
Except all that, does this code works any better:
$unserializearray = unserialize($myserialarray);
then search for array value to change and back to table
$keys = array_keys($unserializearray['dogname'], 'imao', true);
foreach($keys as $key)
{
// find dogname imao and change its visit to once
$unserializearray['visit'][$key] = "once";
}
$update = mysql_real_escap_string(serialize($unserializearray));
//save the update
mysql_query("UPDATE dogdetails SET checkup = '$update' WHERE dogid = '1'");