Question

How do I backup a MySQL database using just queries?
I mean, PHP’s system() function is disables for security reasons, thus I cannot invoke mysqldump.

For table structure I use this:

SHOW CREATE TABLE table_name

But how about table data? Does a predefined SQL command exist? I tried with SELECT ... INTO var_list, but I cannot get this to work (SELECT ... INTO OUTFILE is not suitable for me, as the db host is different from the server I have access to).

Thanks for your help, and sorry for being such a noob, but this is my first question here! 🙂

Answer 1

It should be pretty straightforward to create INSERT statements in your PHP code from a SELECT * FROM table query. Here’s an example:

$db = new PDO('mysql:dbname=DATABASE;host=HOST', 'USER', 'PASSWORD');
$result = $db->query('SELECT * FROM table');

$columns = array();
for($i = 0; $i < $result->columnCount(); $i++) {
  $column = $result->getColumnMeta($i);
  $columns[] = sprintf('`%s`', $column['name']);
}
$colstring = implode(',', $columns);

$rows = $result->fetchAll(PDO::FETCH_NUM);
$inserts = array();
foreach($rows as $r) {
  $values = array_map(function($e) use ($db) {
      return $db->quote($e);
    },
    $r);
  $valstring = implode(',', $values);
  $inserts[] = sprintf('INSERT INTO table (%s) VALUES (%s)',
                       $colstring,
                       $valstring);
}