Since WordPress 4.4. this is now supported by the
delete methods of
wpdb and the ticket #15158 has been closed as fixed.
Thanks to @dmsnell for commenting about that update.
On the other hand, the
null support in
wpdb::prepare() is currently closed as wontfix in ticket #12819.
NULL not supported:
It looks like you will have to write your own custom SQL to update the value with
NULL is not supported by
$wpdb->prepare(), that takes the input through the vsprintf formatting function.
Check out these open Trac tickets:
These tickets are about 4 years old, so I wouldn't hold my breath until this gets supported by the core ;-)
You should take a look at the source as @s_ha_dum suggested.
A possible workaround:
If you're adventurous you can try the following with the
// Add a filter to replace the 'NULL' string with NULL
add_filter( 'query', 'wpse_143405_query' );
'status' => 'NULL',
array( 'id' => 1 )
// Remove the filter again:
remove_filter( 'query', 'wpse_143405_query' );
* Replace the 'NULL' string with NULL
* @param string $query
* @return string $query
function wpse_143405_query( $query )
return str_ireplace( "'NULL'", "NULL", $query );
You might want to use a more unique string than
'NULL' to replace, perhaps