public void setWhereString(String where) {
        this.where = where;
        parent.getModel().setType(SELECT);

        // This replaces the current query
        parent.getModel().clearQueryTree();
    }
Sets the document selection criterion of the query.

@param where the documents to select as a JSON string on the format specified in
       <a href="https://docs.vespa.ai/en/reference/select-reference.html">the select reference doc</a>
container-search/src/main/java/com/yahoo/search/query/Select.java