If type is expressed as "atype[]" (note braces) then it will cause the
placeholder to be re-written dynamically so if the value is an array, it
will create as many placeholders as values are in it. For example:
$query->bind(':id', [1, 2, 3], 'int[]');
Will create 3 int placeholders. When using named placeholders, this method
requires that the placeholders include : e.g. :value.