title: PHP array to postgres array
body: <p>Now php can't work directly wit Postgresql array. For example, php taking postgresql array like
      '{"foo","bar"}'</p>
  
  <p>I need simple php function to create multidimensional postgresql array from php array.</p>
  
  <p>I think that experimental pg_convert() isn't optimal because it needs of extra data to form simple array string for database output, maybe I misunderstood the idea of this function.</p>
  
  <p>For example, I need to convert </p>
  
  <pre><code>$from=array(  array( "par_1_1","par_1_2" ), array( "array_2_1", "array_2_2" )  );
  $to='{{"par_1_1","par_1_2"},{"par_2_1","par_2_2"}}';
  </code></pre>
  
  <p>Can I use array_walk_recursive() to convert the deepest elements of array?</p>