It is removed in 5.0, see #15153.
@@ -38,10 +38,6 @@ search terms, but it is possible to specify other fields in the query syntax:
book.\*:(quick brown)
-* where the field `title` has no value (or is missing):
-
- _missing_:title
* where the field `title` has any non-null value:
_exists_:title