Why a no-indexed field still influence the score in search?

[yejinbiao]

I hava a field named pic_url which is set to index:no

it's just a field to store a url,and i don't want to make it searchable or to influence the score result.
But once i update the pic_url field(only the field,nothing else) ,the score changed... can anyone help? thank you very much.

[jkuang (Jimmy Kuang)]

Try the following:

"pic_url" : {
"type" : "keyword",
"index":    "not_analyzed"
}