public boolean equals(Object other) {
      if (other != null && (other instanceof MCreationMetadata.PK)) {
        MCreationMetadata.PK otherPK = (MCreationMetadata.PK) other;
        return otherPK.id == id;
      }
      return false;
    }
Represents the creation metadata of a materialization.
It includes the database and table name for the materialization,
the set of tables that it uses, the valid transaction list
when it was created, and the creation/rebuild time.
standalone-metastore/metastore-server/src/main/java/org/apache/hadoop/hive/metastore/model/MCreationMetadata.java