Databend 在 Amazon S3 存储后端上的性能
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- Hardware: EC2(c5n.9xlarge, us-east-2), 36 vCPUs
- 存储：S3 (us-east-2)
- Dataset: ontime, 60.8 GB Raw CSV Data, 202687654 records
- Databend: v0.6.98-nightly
- No Local Caching(Data Caching/Query Result Caching)
- Databend is automatic performance optimization with no manual tuning required.
- Analyzing OnTime Datasets with Databend on AWS EC2 and S3 :::
Q1 (0.150 sec., 407.86 million rows/sec., 1.22 GB/sec)
SELECT
DayOfWeek,
count(*) AS c
FROM ontime
WHERE (Year >= 2000) AND (Year <= 2008)
GROUP BY DayOfWeek
ORDER BY c DESC
+-----------+---------+
| DayOfWeek | c |
+-----------+---------+
| 5 | 8732422 |
| 1 | 8730614 |
| 4 | 8710843 |
| 3 | 8685626 |
| 2 | 8639632 |
| 7 | 8274367 |
| 6 | 7514194 |
+-----------+---------+
7 rows in set (0.28 sec)
Read 61000000 rows, 183 MB in 0.150 sec., 407.86 million rows/sec., 1.22 GB/sec.
┌─explain────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┐
│ Projection: DayOfWeek:UInt8, count() as c:UInt64 │
│ Sort: count():UInt64 │
│ AggregatorFinal: groupBy=[[DayOfWeek]], aggr=[[count()]] │
│ AggregatorPartial: groupBy=[[DayOfWeek]], aggr=[[count()]] │
│ Filter: ((Year >= 2000) and (Year <= 2008)) │
│ ReadDataSource: scan schema: [Year:UInt16, DayOfWeek:UInt8], statistics: [read_rows: 61000000, read_bytes: 183000000, partitions_scanned: 61, partitions_total: 203], push_downs: [projections: [0, 4], filters: [((Year >= 2000) AND (Year <= 2008))]] │
└────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┘
Q2 (0.349 sec., 174.92 million rows/sec., 1.22 GB/sec.)
SELECT
DayOfWeek,
count(*) AS c
FROM ontime
WHERE (DepDelay > 10) AND (Year >= 2000) AND (Year <= 2008)
GROUP BY DayOfWeek
ORDER BY c DESC
+-----------+---------+
| DayOfWeek | c |
+-----------+---------+
| 5 | 2175733 |
| 4 | 2012848 |
| 1 | 1898879 |
| 7 | 1880896 |
| 3 | 1757508 |
| 2 | 1665303 |
| 6 | 1510894 |
+-----------+---------+
7 rows in set (0.46 sec)
Read 61000000 rows, 427 MB in 0.349 sec., 174.92 million rows/sec., 1.22 GB/sec.
┌─explain────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┐
│ Projection: DayOfWeek:UInt8, count() as c:UInt64 │
│ Sort: count():UInt64 │
│ AggregatorFinal: groupBy=[[DayOfWeek]], aggr=[[count()]] │
│ AggregatorPartial: groupBy=[[DayOfWeek]], aggr=[[count()]] │
│ Filter: (((DepDelay > 10) and (Year >= 2000)) and (Year <= 2008)) │
│ ReadDataSource: scan schema: [Year:UInt16, DayOfWeek:UInt8, DepDelay:Int32], statistics: [read_rows: 61000000, read_bytes: 427000000, partitions_scanned: 61, partitions_total: 203], push_downs: [projections: [0, 4, 31], filters: [(((DepDelay > 10) AND (Year >= 2000)) AND (Year <= 2008))]] │
└────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┘
Q3 (0.368 sec., 165.96 million rows/sec., 2.82 GB/sec.)
SELECT
Origin,
count(*) AS c
FROM ontime
WHERE (DepDelay > 10) AND (Year >= 2000) AND (Year <= 2008)
GROUP BY Origin
ORDER BY c DESC
LIMIT 10
+--------+--------+
| Origin | c |
+--------+--------+
| ORD | 860911 |
| ATL | 831822 |
| DFW | 614403 |
| LAX | 402671 |
| PHX | 400475 |
| LAS | 362026 |
| DEN | 352893 |
| EWR | 302267 |
| DTW | 296832 |
| IAH | 290729 |
+--------+--------+
10 rows in set (0.47 sec)
Read 61000000 rows, 1.04 GB in 0.368 sec., 165.96 million rows/sec., 2.82 GB/sec.
┌─explain────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┐
│ Limit: 10 │
│ Projection: Origin:String, count() as c:UInt64 │
│ Sort: count():UInt64 │
│ AggregatorFinal: groupBy=[[Origin]], aggr=[[count()]] │
│ AggregatorPartial: groupBy=[[Origin]], aggr=[[count()]] │
│ Filter: (((DepDelay > 10) and (Year >= 2000)) and (Year <= 2008)) │
│ ReadDataSource: scan schema: [Year:UInt16, Origin:String, DepDelay:Int32], statistics: [read_rows: 61000000, read_bytes: 1037000488, partitions_scanned: 61, partitions_total: 203], push_downs: [projections: [0, 14, 31], filters: [(((DepDelay > 10) AND (Year >= 2000)) AND (Year <= 2008))]] │
└────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┘
Q4 (0.126 sec., 63.48 million rows/sec., 1.02 GB/sec.)
SELECT
IATA_CODE_Reporting_Airline AS Carrier,
count()
FROM ontime
WHERE (DepDelay > 10) AND (Year = 2007)
GROUP BY Carrier
ORDER BY count() DESC
+---------+---------+
| Carrier | count() |
+---------+---------+
| WN | 296451 |
| AA | 179769 |
| MQ | 152293 |
| OO | 147019 |
| US | 140199 |
| UA | 135061 |
| XE | 108571 |
| EV | 104055 |
| NW | 102206 |
| DL | 98427 |
| CO | 81039 |
| YV | 79553 |
| FL | 64583 |
| OH | 60532 |
| AS | 54326 |
| B6 | 53716 |
| 9E | 48578 |
| F9 | 24100 |
| AQ | 6764 |
| HA | 4059 |
+---------+---------+
20 rows in set (0.28 sec)
Read 8000000 rows, 128 MB in 0.126 sec., 63.48 million rows/sec., 1.02 GB/sec.
┌─explain────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┐
│ Projection: IATA_CODE_Reporting_Airline as Carrier:String, count():UInt64 │
│ Sort: count():UInt64 │
│ AggregatorFinal: groupBy=[[IATA_CODE_Reporting_Airline]], aggr=[[count()]] │
│ AggregatorPartial: groupBy=[[IATA_CODE_Reporting_Airline]], aggr=[[count()]] │
│ Filter: ((DepDelay > 10) and (Year = 2007)) │
│ ReadDataSource: scan schema: [Year:UInt16, IATA_CODE_Reporting_Airline:String, DepDelay:Int32], statistics: [read_rows: 8000000, read_bytes: 128000064, partitions_scanned: 8, partitions_total: 203], push_downs: [projections: [0, 8, 31], filters: [((DepDelay > 10) AND (Year = 2007))]] │
└────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┘
Q5 (0.151 sec., 52.81 million rows/sec., 844.98 MB/sec)
SELECT
IATA_CODE_Reporting_Airline AS Carrier,
avg(CAST(DepDelay > 10, Int8)) * 1000 AS c3
FROM ontime
WHERE Year = 2007
GROUP BY Carrier
ORDER BY c3 DESC
+---------+--------------------+
| Carrier | c3 |
+---------+--------------------+
| EV | 363.53123668047823 |
| AS | 339.1453631738303 |
| US | 288.8039271022377 |
| AA | 283.6112877194699 |
| MQ | 281.7663100792978 |
| B6 | 280.5745625489684 |
| UA | 275.63356884257615 |
| YV | 270.25567158804466 |
| OH | 256.4567516268981 |
| WN | 253.62165713752844 |
| CO | 250.77750030171651 |
| XE | 249.71881878589517 |
| NW | 246.56113247419944 |
| F9 | 246.52209492635023 |
| OO | 245.90051515354253 |
| FL | 245.4143692596491 |
| DL | 206.82764258051773 |
| 9E | 187.66780889391967 |
| AQ | 145.9016393442623 |
| HA | 72.25634178905207 |
+---------+--------------------+
20 rows in set (0.30 sec)
Read 8000000 rows, 128 MB in 0.151 sec., 52.81 million rows/sec., 844.98 MB/sec.
┌─explain────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┐
│ Projection: IATA_CODE_Reporting_Airline as Carrier:String, (avg(cast((DepDelay > 10) as Int8)) * 1000) as c3:Float64 │
│ Sort: (avg(cast((DepDelay > 10) as Int8)) * 1000):Float64 │
│ Expression: IATA_CODE_Reporting_Airline:String, (avg(cast((DepDelay > 10) as Int8)) * 1000):Float64 (Before OrderBy) │
│ AggregatorFinal: groupBy=[[IATA_CODE_Reporting_Airline]], aggr=[[avg(cast((DepDelay > 10) as Int8))]] │
│ AggregatorPartial: groupBy=[[IATA_CODE_Reporting_Airline]], aggr=[[avg(cast((DepDelay > 10) as Int8))]] │
│ Expression: IATA_CODE_Reporting_Airline:String, cast((DepDelay > 10) as Int8):Int8 (Before GroupBy) │
│ Filter: (Year = 2007) │
│ ReadDataSource: scan schema: [Year:UInt16, IATA_CODE_Reporting_Airline:String, DepDelay:Int32], statistics: [read_rows: 8000000, read_bytes: 128000064, partitions_scanned: 8, partitions_total: 203], push_downs: [projections: [0, 8, 31], filters: [(Year = 2007)]] │
└────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┘
Q6 (0.337 sec., 180.83 million rows/sec., 2.89 GB/sec.)
SELECT
IATA_CODE_Reporting_Airline AS Carrier,
avg(CAST(DepDelay > 10, Int8)) * 1000 AS c3
FROM ontime
WHERE (Year >= 2000) AND (Year <= 2008)
GROUP BY Carrier
ORDER BY c3 DESC
+---------+--------------------+
| Carrier | c3 |
+---------+--------------------+
| AS | 293.05649076611434 |
| EV | 282.0709981074399 |
| YV | 270.3897636688929 |
| B6 | 257.40594891667007 |
| FL | 249.28742951361826 |
| XE | 246.59005902424192 |
| MQ | 245.3695989400477 |
| WN | 233.38127235928863 |
| DH | 227.11013827345042 |
| F9 | 226.08455653226812 |
| UA | 224.42824657703645 |
| OH | 215.52882835147614 |
| AA | 211.97122176454556 |
| US | 206.60330294168244 |
| HP | 205.31690167066455 |
| OO | 202.4243177198239 |
| NW | 191.7393936377831 |
| TW | 188.6912623180138 |
| DL | 187.84162871590732 |
| CO | 187.71301306878976 |
| 9E | 181.6396991511518 |
| RU | 181.46244295416398 |
| TZ | 176.8928125899626 |
| AQ | 145.65911608293766 |
| HA | 79.38672451825789 |
+---------+--------------------+
25 rows in set (0.44 sec)
Read 61000000 rows, 976 MB in 0.337 sec., 180.83 million rows/sec., 2.89 GB/sec.
┌─explain────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┐
│ Projection: IATA_CODE_Reporting_Airline as Carrier:String, (avg(cast((DepDelay > 10) as Int8)) * 1000) as c3:Float64 │
│ Sort: (avg(cast((DepDelay > 10) as Int8)) * 1000):Float64 │
│ Expression: IATA_CODE_Reporting_Airline:String, (avg(cast((DepDelay > 10) as Int8)) * 1000):Float64 (Before OrderBy) │
│ AggregatorFinal: groupBy=[[IATA_CODE_Reporting_Airline]], aggr=[[avg(cast((DepDelay > 10) as Int8))]] │
│ AggregatorPartial: groupBy=[[IATA_CODE_Reporting_Airline]], aggr=[[avg(cast((DepDelay > 10) as Int8))]] │
│ Expression: IATA_CODE_Reporting_Airline:String, cast((DepDelay > 10) as Int8):Int8 (Before GroupBy) │
│ Filter: ((Year >= 2000) and (Year <= 2008)) │
│ ReadDataSource: scan schema: [Year:UInt16, IATA_CODE_Reporting_Airline:String, DepDelay:Int32], statistics: [read_rows: 61000000, read_bytes: 976000488, partitions_scanned: 61, partitions_total: 203], push_downs: [projections: [0, 8, 31], filters: [((Year >= 2000) AND (Year <= 2008))]] │
└────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┘
Q7 (0.331 sec., 184.12 million rows/sec., 2.95 GB/sec.)
SELECT
IATA_CODE_Reporting_Airline AS Carrier,
avg(DepDelay) * 1000 AS c3
FROM ontime
WHERE (Year >= 2000) AND (Year <= 2008)
GROUP BY Carrier
+---------+--------------------+
| Carrier | c3 |
+---------+--------------------+
| HA | 6851.555976883671 |
| DH | 15311.949983190174 |
| TW | 10842.722114986364 |
| WN | 10484.932610056378 |
| OH | 12655.103820799075 |
| F9 | 11232.889558936127 |
| 9E | 13091.087573576122 |
| EV | 16374.703330010156 |
| RU | 12556.249210602802 |
| DL | 10943.456441165357 |
| B6 | 16789.739456036365 |
| TZ | 12618.760195758565 |
| CO | 12671.595978518368 |
| AA | 13508.78515494305 |
| NW | 11717.623092632819 |
| FL | 15192.451732538268 |
| OO | 11600.594852741107 |
| US | 11868.7097884053 |
| MQ | 14125.201554023559 |
| HP | 11625.682112859839 |
| AQ | 7323.278123603293 |
| UA | 14594.243159716054 |
| XE | 17092.548853057146 |
| AS | 14735.545887755581 |
| YV | 17971.53933699898 |
+---------+--------------------+
25 rows in set (0.49 sec)
Read 61000000 rows, 976 MB in 0.331 sec., 184.12 million rows/sec., 2.95 GB/sec.
┌─explain────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┐
│ Projection: IATA_CODE_Reporting_Airline as Carrier:String, (avg(DepDelay) * 1000) as c3:Float64 │
│ Expression: IATA_CODE_Reporting_Airline:String, (avg(DepDelay) * 1000):Float64 (Before Projection) │
│ AggregatorFinal: groupBy=[[IATA_CODE_Reporting_Airline]], aggr=[[avg(DepDelay)]] │
│ AggregatorPartial: groupBy=[[IATA_CODE_Reporting_Airline]], aggr=[[avg(DepDelay)]] │
│ Filter: ((Year >= 2000) and (Year <= 2008)) │
│ ReadDataSource: scan schema: [Year:UInt16, IATA_CODE_Reporting_Airline:String, DepDelay:Int32], statistics: [read_rows: 61000000, read_bytes: 976000488, partitions_scanned: 61, partitions_total: 203], push_downs: [projections: [0, 8, 31], filters: [((Year >= 2000) AND (Year <= 2008))]] │
└────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┘
Q8 (0.799 sec., 253.64 million rows/sec., 1.52 GB/sec.)
SELECT
Year,
avg(DepDelay)
FROM ontime
GROUP BY Year
+------+--------------------+
| Year | avg(DepDelay) |
+------+--------------------+
| 2010 | 13.202976628175891 |
| 2002 | 9.97856700710386 |
| 2021 | 15.289615417399649 |
| 2004 | 11.936799840656898 |
| 2016 | 14.643883269504837 |
| 2017 | 15.70225324299191 |
| 2007 | 15.431738868356579 |
| 2012 | 13.155971481255131 |
| 1994 | 7.758752042452116 |
| 2001 | 10.895474364001354 |
| 2014 | 15.513697266113969 |
| 1997 | 9.919225483813925 |
| 2008 | 14.654588068064287 |
| 2009 | 13.168984006133062 |
| 1992 | 6.687364706154975 |
| 1998 | 10.884314711941435 |
| 1995 | 9.328649903752932 |
| 2020 | 10.624498278073712 |
| 2006 | 14.237297887039372 |
| 2019 | 16.983263489524507 |
| 2005 | 12.60167890747495 |
| 1999 | 11.567390524113748 |
| 1991 | 6.940411174086677 |
| 1989 | 8.81845473300008 |
| 2018 | 16.16188254545747 |
| 2011 | 13.496191548097778 |
| 2000 | 13.456897681824556 |
| 2003 | 9.778465263372038 |
| 1990 | 7.966702606180775 |
| 2015 | 14.638336410280733 |
| 2013 | 14.901210490900201 |
| 1993 | 7.207721091071671 |
| 1988 | 7.345867511864449 |
| 1996 | 11.14468468976826 |
| 1987 | 8.600789281505321 |
+------+--------------------+
35 rows in set (0.92 sec)
Read 202687655 rows, 1.22 GB in 0.799 sec., 253.64 million rows/sec., 1.52 GB/sec.
┌─explain──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┐
│ Projection: Year:UInt16, avg(DepDelay):Float64 │
│ AggregatorFinal: groupBy=[[Year]], aggr=[[avg(DepDelay)]] │
│ AggregatorPartial: groupBy=[[Year]], aggr=[[avg(DepDelay)]] │
│ ReadDataSource: scan schema: [Year:UInt16, DepDelay:Int32], statistics: [read_rows: 202687654, read_bytes: 1216125924, partitions_scanned: 203, partitions_total: 203], push_downs: [projections: [0, 31]] │
└──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┘
Q9 (0.330 sec., 613.82 million rows/sec., 1.23 GB/sec.)
SELECT
Year,
count(*) AS c1
FROM ontime
GROUP BY Year
+------+---------+
| Year | c1 |
+------+---------+
| 2016 | 5617658 |
| 2019 | 7422037 |
| 1996 | 5351983 |
| 2020 | 4688354 |
| 2004 | 7129270 |
| 2002 | 5271359 |
| 2018 | 7213446 |
| 2000 | 5683047 |
| 2014 | 5819811 |
| 1990 | 5270893 |
| 1992 | 5092157 |
| 1991 | 5076925 |
| 2003 | 6488540 |
| 1995 | 5327435 |
| 2008 | 7009726 |
| 1999 | 5527884 |
| 2007 | 7455458 |
| 2001 | 5967780 |
| 2010 | 6450117 |
| 2013 | 6369482 |
| 2021 | 5443512 |
| 2009 | 6450285 |
| 2006 | 7141922 |
| 1994 | 5180048 |
| 1993 | 5070501 |
| 2015 | 5819079 |
| 1997 | 5411843 |
| 1988 | 5202096 |
| 1989 | 5041200 |
| 2017 | 5674621 |
| 2005 | 7140596 |
| 2012 | 6096762 |
| 2011 | 6085281 |
| 1987 | 1311826 |
| 1998 | 5384721 |
+------+---------+
35 rows in set (0.48 sec)
Read 202687655 rows, 405.38 MB in 0.330 sec., 613.82 million rows/sec., 1.23 GB/sec.
┌─explain─────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┐
│ Projection: Year:UInt16, count() as c1:UInt64 │
│ AggregatorFinal: groupBy=[[Year]], aggr=[[count()]] │
│ AggregatorPartial: groupBy=[[Year]], aggr=[[count()]] │
│ ReadDataSource: scan schema: [Year:UInt16], statistics: [read_rows: 202687654, read_bytes: 405375308, partitions_scanned: 203, partitions_total: 203], push_downs: [projections: [0]] │
└─────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┘
Q10 (0.592 sec., 342.12 million rows/sec., 2.39 GB/sec.)
SELECT avg(cnt)
FROM
(
SELECT
Year,
Month,
count(*) AS cnt
FROM ontime
WHERE DepDel15 = 1
GROUP BY
Year,
Month
) AS a
+-------------------+
| avg(cnt) |
+-------------------+
| 81342.93170731707 |
+-------------------+
1 row in set (0.69 sec)
Read 202687655 rows, 1.42 GB in 0.592 sec., 342.12 million rows/sec., 2.39 GB/sec.
┌─explain────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┐
│ Projection: avg(cnt):Float64 │
│ AggregatorFinal: groupBy=[[]], aggr=[[avg(cnt)]] │
│ AggregatorPartial: groupBy=[[]], aggr=[[avg(cnt)]] │
│ Projection: Year:UInt16, Month:UInt8, count() as cnt:UInt64 │
│ AggregatorFinal: groupBy=[[Year, Month]], aggr=[[count()]] │
│ AggregatorPartial: groupBy=[[Year, Month]], aggr=[[count()]] │
│ Filter: (DepDel15 = 1) │
│ ReadDataSource: scan schema: [Year:UInt16, Month:UInt8, DepDel15:Int32], statistics: [read_rows: 202687654, read_bytes: 1418813578, partitions_scanned: 203, partitions_total: 203], push_downs: [projections: [0, 2, 33], filters: [(DepDel15 = 1)]] │
└────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┘
Q11 (0.426 sec., 475.6 million rows/sec., 1.43 GB/sec.)
SELECT avg(c1)
FROM
(
SELECT
Year,
Month,
count(*) AS c1
FROM ontime
GROUP BY
Year,
Month
) AS a
-------------------+
| avg(c1) |
+-------------------+
| 494360.1341463415 |
+-------------------+
1 row in set (0.57 sec)
Read 202687655 rows, 608.06 MB in 0.426 sec., 475.6 million rows/sec., 1.43 GB/sec.
┌─explain───────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┐
│ Projection: avg(c1):Float64 │
│ AggregatorFinal: groupBy=[[]], aggr=[[avg(c1)]] │
│ AggregatorPartial: groupBy=[[]], aggr=[[avg(c1)]] │
│ Projection: Year:UInt16, Month:UInt8, count() as c1:UInt64 │
│ AggregatorFinal: groupBy=[[Year, Month]], aggr=[[count()]] │
│ AggregatorPartial: groupBy=[[Year, Month]], aggr=[[count()]] │
│ ReadDataSource: scan schema: [Year:UInt16, Month:UInt8], statistics: [read_rows: 202687654, read_bytes: 608062962, partitions_scanned: 203, partitions_total: 203], push_downs: [projections: [0, 2]] │
└───────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┘
Q12 (2.704 sec., 74.95 million rows/sec., 3.17 GB/sec.)
SELECT
OriginCityName,
DestCityName,
count(*) AS c
FROM ontime
GROUP BY
OriginCityName,
DestCityName
ORDER BY c DESC
LIMIT 10
+-------------------+-------------------+--------+
| OriginCityName | DestCityName | c |
+-------------------+-------------------+--------+
| San Francisco, CA | Los Angeles, CA | 518850 |
| Los Angeles, CA | San Francisco, CA | 515980 |
| New York, NY | Chicago, IL | 457899 |
| Chicago, IL | New York, NY | 450557 |
| Chicago, IL | Minneapolis, MN | 439491 |
| Minneapolis, MN | Chicago, IL | 435311 |
| Los Angeles, CA | Las Vegas, NV | 431245 |
| Las Vegas, NV | Los Angeles, CA | 425188 |
| New York, NY | Boston, MA | 421854 |
| Boston, MA | New York, NY | 418572 |
+-------------------+-------------------+--------+
10 rows in set (2.84 sec)
Read 202687655 rows, 8.58 GB in 2.704 sec., 74.95 million rows/sec., 3.17 GB/sec.
┌─explain──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┐
│ Limit: 10 │
│ Projection: OriginCityName:String, DestCityName:String, count() as c:UInt64 │
│ Sort: count():UInt64 │
│ AggregatorFinal: groupBy=[[OriginCityName, DestCityName]], aggr=[[count()]] │
│ AggregatorPartial: groupBy=[[OriginCityName, DestCityName]], aggr=[[count()]] │
│ ReadDataSource: scan schema: [OriginCityName:String, DestCityName:String], statistics: [read_rows: 202687654, read_bytes: 8577734415, partitions_scanned: 203, partitions_total: 203], push_downs: [projections: [15, 24]] │
└──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┘
Q13 (1.110 sec., 182.62 million rows/sec., 3.86 GB/sec.)
SELECT
OriginCityName,
count(*) AS c
FROM ontime
GROUP BY OriginCityName
ORDER BY c DESC
LIMIT 10
+-----------------------+----------+
| OriginCityName | c |
+-----------------------+----------+
| Chicago, IL | 12592771 |
| Atlanta, GA | 10944276 |
| Dallas/Fort Worth, TX | 9045390 |
| Houston, TX | 6868696 |
| Los Angeles, CA | 6726120 |
| New York, NY | 6336818 |
| Denver, CO | 6311909 |
| Phoenix, AZ | 5678632 |
| Washington, DC | 5022328 |
| San Francisco, CA | 4696887 |
+-----------------------+----------+
10 rows in set (1.24 sec)
Read 202687655 rows, 4.29 GB in 1.110 sec., 182.62 million rows/sec., 3.86 GB/sec.
┌─explain─────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┐
│ Limit: 10 │
│ Projection: OriginCityName:String, count() as c:UInt64 │
│ Sort: count():UInt64 │
│ AggregatorFinal: groupBy=[[OriginCityName]], aggr=[[count()]] │
│ AggregatorPartial: groupBy=[[OriginCityName]], aggr=[[count()]] │
│ ReadDataSource: scan schema: [OriginCityName:String], statistics: [read_rows: 202687654, read_bytes: 4288897378, partitions_scanned: 203, partitions_total: 203], push_downs: [projections: [15]] │
└─────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┘
Q14
SELECT
count(*)
FROM ontime;
+-----------+
| count() |
+-----------+
| 202687654 |
+-----------+
1 row in set (0.15 sec)
┌─explain─────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┐
│ Projection: count():UInt64 │
│ Projection: 202687654 as count():UInt64 │
│ Expression: 202687654:UInt64 (Exact Statistics) │
│ ReadDataSource: scan schema: [dummy:UInt8], statistics: [read_rows: 1, read_bytes: 1, partitions_scanned: 1, partitions_total: 1] │
└─────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┘