public boolean needMatchQuery() {
        return analyzer != null;
    }
The analyzer policy appointed to fuzzy query, especially for ElasticSearch.
When it is null, it means no need to build match query, no `copy_to` column, and no analyzer assigned.
oap-server/server-core/src/main/java/org/apache/skywalking/oap/server/core/storage/model/ElasticSearchExtension.java