Approaches for same server or not

Hi @jasdeepkhalsa,
I can't get the reason why you use 2 different approaches if the comparison is between same servers or different.
I mean this code in method getDiff of TableData:

```
if ($server1 == $server2) {
  return $this->localTableData->getDiff($table, $sourceKey);
} else {
  return $this->distTableData->getDiff($table, $sourceKey);
}
```

Please, can you help me to understand?
