Question

I tried this as a test purpose. And I don’t know why is this happening. That’s I need help from the experts. Thanks.

Lets assume that we have a database and we have established connection with the database. Let’s assume there is a table named table. Inside the table there are two columns- id and name. there are 5 rows of data in the table. Table structure is

| id |  name  |
---------------
| 1  |  name1 |
| 2  |  name2 |
| 3  |  name3 |
| 4  |  name4 |
| 5  |  name5 |

Now my code goes here-

    <?php
    mysql_connect("localhost","root","") or die(mysql_error());
    mysql_select_db("test") or die(mysql_error());

    $result  = mysql_query("SELECT * FROM `table`");

    /* let's store this value in two different variables. */

    $result1 = $result;
    $result2 = $result;

    /* let's perform mysql_fetch_array() and mysql_fetch_row() functions */
    $result22 = mysql_fetch_row($result);
    var_dump($result22);
    $result11 = mysql_fetch_array($result);
    var_dump($result11);
?>

it results :

array
  0 => string '1' (length=1)
  1 => string 'name1' (length=5)

array
  0 => string '2' (length=1)
  'id' => string '2' (length=1)
  1 => string 'name2' (length=5)
  'name' => string 'name2' (length=5)

If i alter the order of the functions it results :

array
  0 => string '1' (length=1)
  'id' => string '1' (length=1)
  1 => string 'name1' (length=5)
  'name' => string 'name1' (length=5)

array
  0 => string '2' (length=1)
  1 => string 'name2' (length=5)

It seems that when I perform a function upon the result of mysql_query, that function simply removes the first row from the result even if it is stored in other variable before
calling the function.

If i add a condition WHERE id = 1 then the second function returns false, like:

array
  0 => string '1' (length=1)
  'id' => string '1' (length=1)
  1 => string 'name1' (length=5)
  'name' => string 'name1' (length=5)

boolean false

Why is this happening? Thanks in advance.

Answer 1

This line doesn’t return the “result”, it returns a resource object that you can use to access the result:

$result = mysql_query("SELECT * FROM `table`");

These lines just assign the same resource to two different variables:

$result1 = $result;
$result2 = $result;

You shouldn’t think of it as two separate result sets. You’ve just given two different names for the same resource.