misc(clickhouse): use final instead of manually handling duplicate rows when fetching balances from clickhouse

Author: peterbitfly

db/bigtable.go

@@ -808,25 +808,17 @@ func (bigtable *Bigtable) getValidatorBalanceHistoryClickhouse(validators []uint
 				epoch_timestamp, 
 				balance, 
 				effective_balance
-			FROM legacy_validator_epoch_balances WHERE epoch_timestamp >= ? AND epoch_timestamp <= ? AND validator_index IN (?) ORDER BY epoch_timestamp ASC`
+			FROM legacy_validator_epoch_balances FINAL WHERE epoch_timestamp >= ? AND epoch_timestamp <= ? AND validator_index IN (?) ORDER BY epoch_timestamp ASC`
 
 	err := ClickhouseReaderDb.Select(&rows, query, startEpochTs, endEpochTs, validators)
 	if err != nil {
 		logger.Error(err)
 		return nil, err
 	}
 
-	// the query might return duplicate rows, so we need to deduplicate them
-	// the key is the validator index and the epoch, so we can use that to deduplicate
-	seen := make(map[string]bool)
 	res := make(map[uint64][]*types.ValidatorBalance, len(validators))
 	for _, r := range rows {
 		epoch := uint64(utils.TimeToEpoch(r.EpochTimestamp))
-		seenKey := fmt.Sprintf("%d:%d", r.ValidatorIndex, epoch)
-		if seen[seenKey] {
-			continue
-		}
-		seen[seenKey] = true
 		if res[r.ValidatorIndex] == nil {
 			res[r.ValidatorIndex] = make([]*types.ValidatorBalance, 0)
 		}