public void setCreateMissingPath(boolean createMissingPath) {
        this.createMissingPath = createMissingPath;
    }
If set to true, and any part of the field path specified does not exist (except for array indexes), we create the path as necessary.
Default is true.
document/src/main/java/com/yahoo/document/fieldpathupdate/AssignFieldPathUpdate.java