@Override
  public boolean equals(Object o) {
    if (this == o) return true;
    if (o == null || getClass() != o.getClass()) return false;
    SchemaAwareCacheKey that = (SchemaAwareCacheKey) o;
    return schemaHash == that.schemaHash && Objects.equals(fileId, that.fileId);
  }
Cache key that stores schema hash. Useful caching serdes that do not have a self-describing schema built in.
ql/src/java/org/apache/hadoop/hive/llap/SchemaAwareCacheKey.java