static SelectTraceIdsFromSpan.Factory initialiseSelectTraceIdsFromSpan(CqlSession session) {
    try {
      return new SelectTraceIdsFromSpan.Factory(session);
    } catch (DriverException ex) {
      LOG.warn("failed to prepare annotation_query index statements: {}", ex.getMessage(), ex);
      return null;
    }
  }
This makes it possible to safely drop the annotations_query SASI.

<p>If dropped, trying to search by annotation in the UI will throw an IllegalStateException.
zipkin-storage/cassandra/src/main/java/zipkin2/storage/cassandra/CassandraSpanStore.java