How do you call filter only on the column filter?

[primeUser99282]

I'm trying to follow the date picker example in showcase:

<p:datePicker selectionMode="range" onchange="PF('customersTable').filter()" />

However, when I have a global filter field on the form, it always gives me this warning:

"cannot validate component with empty value:"

Is this just a bug and/or can I get around it by just calling .filter() on the date column filter instead of the entire table?

[Melloware]

No filter() is for the entire table.

[tandraschko]

"cannot validate component with empty value:" is just a warning from MyFaces, it should not break anything