@SuppressWarnings("squid:S2245")
  public static long generateTemporaryId() {
    return -1 * ThreadLocalRandom.current().nextLong();
  }
A helper method to return SQL's 'IS NULL'
clause whenever input is NULL.
@param input A string to be compared to null.
@return String
standalone-metastore/metastore-server/src/main/java/org/apache/hadoop/hive/metastore/txn/TxnUtils.java