shell> curl -X DELETE --header 'If-Match: "_UWx9Dbq---"' --dump - http://localhost:8529/_api/document/products/9750
HTTP/1.1 412 Precondition Failed
content-type: application/json; charset=utf-8
etag: "_UWx9Dbm---"
{
"error" : true,
"code" : 412,
"errorNum" : 1200,
"errorMessage" : "precondition failed",
"_id" : "products/9750",
"_key" : "9750",
"_rev" : "_UWx9Dbm---"
}