array to string conversion error, need to explode and then implode - php

Question

I want to explode an array, read each value and print them back in an array...
I dont understand where i am getting wrong. Please help me..this is my code..
I am getting an array to string conversion error
$query="SELECT categories FROM shops";
$result = mysql_query($query);
while($column = mysql_fetch_assoc($result)){
$categories=explode(",",$column['categories']);
foreach($categories as $value){
$new_query="SELECT name from categories where id='$value'";
$name = mysql_query($new_query);
$name_column= mysql_fetch_assoc($name);
array_push($shops_list,$name_column);
}
}
echo implode(",",$shops_list);

Answer 1

$shop_list is not defined, before using it in this line array_push($shops_list,$name_column);. And, this line
array_push($shops_list,$name_column);
needs to be, as you need to mention the key name,
array_push($shops_list,$name_column['name']); //or better
$shop_list[] = $name_column['name'];

Answer 2

Several issues:
$name_column = mysql_fetch_assoc($name);
$name_column = $name_column['name'];
name_column is an array.
shops_list is never initialized.
You should use [] instead of array_push.

Answer 3

The other guys hit it on the nose, but when you did your array push on $name_column, since $name_column is an array, you end up with:
Array
(
[0] => Array
(
[name] => boo
)
)
Obviously doing an implode on that is going to not work.
That being said, what you really need to do here is not keep your category mappings as a comma delimited string in the database. Standard DB architecture dictates you use a mapping table.
Table shops
Table categories
Table shop_category_map that has shop_id and category_id

Answer 4

use group_concat to retrieve values. and after getting the result, use them directly for searching. like
$result_array = explode(",",$row['category']);
foreach($result_array as $ra)
{
//sql command. fetch here.
$new_query="SELECT name from categories where id='$value'";
$name = mysql_query($new_query);
$name_column= mysql_fetch_assoc($name);
$shops_list[] = $name_column;
}
try else go for better solution

Answer 5

// explode an array and then implode until a particular index of an array
$a = '192.168.3.250';
$b = explode('.',$a);
$ar = array();
for($i=0;$i<=2;$i++)
{
array_push($ar,$b[$i]);
}
$C = implode($ar,'.');
print_r($C);