I use a mysql spatial column (POINT) with a spatial index on it. This kind of index doesn't allow a default value nor a NULL value. That's why we have to set it when we insert a row.

Problem : the value is binary and all the ways I tried were leading to this error : SQLSTATE[22003]: Numeric value out of range: 1416 Cannot get geometry object from data you send to the GEOMETRY field

I tried :

// $row is an instance of Zend_Db_Table_Row
$row->point = 0;
$row->save();

$row->point = "\0";
$row->save();

$row->point = NULL;
$row->save();

$row->point = 0x00000000010100000000000000000000000000000000000000; // The hexa of POINT(0,0)
$row->save();

$row->point = "0x00000000010100000000000000000000000000000000000000"; // The hexa of POINT(0,0)
$row->save();

$row->point = "PointFromWKB(Point(0, 0)"; 
$row->save();