ClickHouse介绍-示例


示例

GitHub 事件数据集

数据集包含了GitHub上从2011年到2020年12月6日的所有事件,大小为31亿条记录。下载大小为75 GB,如果存储在使用lz4压缩的表中,则需要多达200 GB的磁盘空间。

 

Anonymized Yandex.Metrica Data

数据集由两个表组成,包含关于Yandex.Metrica的hits(hits_v1)和visit(visits_v1)的匿名数据。你可以阅读更多关于Yandex的信息。在ClickHouse历史的Metrica部分。

数据集由两个表组成,他们中的任何一个都可以下载作为一个压缩tsv.xz的文件或准备的分区。除此之外,一个扩展版的hits表包含1亿行TSV在https://datasets.clickhouse.com/hits/tsv/hits_100m_obfuscated_v1.tsv.xz,准备分区在https://datasets.clickhouse.com/hits/partitions/hits_100m_obfuscated_v1.tar.xz。

从准备好的分区获取表?

下载和导入hits表:

curl -O https://datasets.clickhouse.com/hits/partitions/hits_v1.tar
tar xvf hits_v1.tar -C /var/lib/clickhouse # path to ClickHouse data directory
# check permissions on unpacked data, fix if required
sudo service clickhouse-server restart
clickhouse-client --query "SELECT COUNT(*) FROM datasets.hits_v1"

从TSV压缩文件获取表?

从TSV压缩文件下载并导入hits:

curl https://datasets.clickhouse.com/hits/tsv/hits_v1.tsv.xz | unxz --threads=`nproc` > hits_v1.tsv
# now create table
clickhouse-client --query "CREATE DATABASE IF NOT EXISTS datasets"
clickhouse-client --query "CREATE TABLE datasets.hits_v1 ( WatchID UInt64,  JavaEnable UInt8,  Title String,  GoodEvent Int16,  EventTime DateTime,  EventDate Date,  CounterID UInt32,  ClientIP UInt32,  ClientIP6 FixedString(16),  RegionID UInt32,  UserID UInt64,  CounterClass Int8,  OS UInt8,  UserAgent UInt8,  URL String,  Referer String,  URLDomain String,  RefererDomain String,  Refresh UInt8,  IsRobot UInt8,  RefererCategories Array(UInt16),  URLCategories Array(UInt16), URLRegions Array(UInt32),  RefererRegions Array(UInt32),  ResolutionWidth UInt16,  ResolutionHeight UInt16,  ResolutionDepth UInt8,  FlashMajor UInt8, FlashMinor UInt8,  FlashMinor2 String,  NetMajor UInt8,  NetMinor UInt8, UserAgentMajor UInt16,  UserAgentMinor FixedString(2),  CookieEnable UInt8, JavascriptEnable UInt8,  IsMobile UInt8,  MobilePhone UInt8,  MobilePhoneModel String,  Params String,  IPNetworkID UInt32,  TraficSourceID Int8, SearchEngineID UInt16,  SearchPhrase String,  AdvEngineID UInt8,  IsArtifical UInt8,  WindowClientWidth UInt16,  WindowClientHeight UInt16,  ClientTimeZone Int16,  ClientEventTime DateTime,  SilverlightVersion1 UInt8, SilverlightVersion2 UInt8,  SilverlightVersion3 UInt32,  SilverlightVersion4 UInt16,  PageCharset String,  CodeVersion UInt32,  IsLink UInt8,  IsDownload UInt8,  IsNotBounce UInt8,  FUniqID UInt64,  HID UInt32,  IsOldCounter UInt8, IsEvent UInt8,  IsParameter UInt8,  DontCountHits UInt8,  WithHash UInt8, HitColor FixedString(1),  UTCEventTime DateTime,  Age UInt8,  Sex UInt8,  Income UInt8,  Interests UInt16,  Robotness UInt8,  GeneralInterests Array(UInt16), RemoteIP UInt32,  RemoteIP6 FixedString(16),  WindowName Int32,  OpenerName Int32,  HistoryLength Int16,  BrowserLanguage FixedString(2),  BrowserCountry FixedString(2),  SocialNetwork String,  SocialAction String,  HTTPError UInt16, SendTiming Int32,  DNSTiming Int32,  ConnectTiming Int32,  ResponseStartTiming Int32,  ResponseEndTiming Int32,  FetchTiming Int32,  RedirectTiming Int32, DOMInteractiveTiming Int32,  DOMContentLoadedTiming Int32,  DOMCompleteTiming Int32,  LoadEventStartTiming Int32,  LoadEventEndTiming Int32, NSToDOMContentLoadedTiming Int32,  FirstPaintTiming Int32,  RedirectCount Int8, SocialSourceNetworkID UInt8,  SocialSourcePage String,  ParamPrice Int64, ParamOrderID String,  ParamCurrency FixedString(3),  ParamCurrencyID UInt16, GoalsReached Array(UInt32),  OpenstatServiceName String,  OpenstatCampaignID String,  OpenstatAdID String,  OpenstatSourceID String,  UTMSource String, UTMMedium String,  UTMCampaign String,  UTMContent String,  UTMTerm String, FromTag String,  HasGCLID UInt8,  RefererHash UInt64,  URLHash UInt64,  CLID UInt32,  YCLID UInt64,  ShareService String,  ShareURL String,  ShareTitle String,  ParsedParams Nested(Key1 String,  Key2 String, Key3 String, Key4 String, Key5 String,  ValueDouble Float64),  IslandID FixedString(16),  RequestNum UInt32,  RequestTry UInt8) ENGINE = MergeTree() PARTITION BY toYYYYMM(EventDate) ORDER BY (CounterID, EventDate, intHash32(UserID)) SAMPLE BY intHash32(UserID) SETTINGS index_granularity = 8192"
# import data
cat hits_v1.tsv | clickhouse-client --query "INSERT INTO datasets.hits_v1 FORMAT TSV" --max_insert_block_size=100000
# optionally you can optimize table
clickhouse-client --query "OPTIMIZE TABLE datasets.hits_v1 FINAL"
clickhouse-client --query "SELECT COUNT(*) FROM datasets.hits_v1"

查询示例?

使用教程是以Yandex.Metrica数据集开始教程。

可以在ClickHouse的stateful tests 中找到对这些表的查询的其他示例(它们被命名为test.histstest.visits)。

 

Star Schema Benchmark

编译 dbgen:

$ git clone git@github.com:vadimtk/ssb-dbgen.git
$ cd ssb-dbgen
$ make

在 ClickHouse 中创建数据表:

CREATE TABLE customer
(
        C_CUSTKEY       UInt32,
        C_NAME          String,
        C_ADDRESS       String,
        C_CITY          LowCardinality(String),
        C_NATION        LowCardinality(String),
        C_REGION        LowCardinality(String),
        C_PHONE         String,
        C_MKTSEGMENT    LowCardinality(String)
)
ENGINE = MergeTree ORDER BY (C_CUSTKEY);

CREATE TABLE lineorder
(
    LO_ORDERKEY             UInt32,
    LO_LINENUMBER           UInt8,
    LO_CUSTKEY              UInt32,
    LO_PARTKEY              UInt32,
    LO_SUPPKEY              UInt32,
    LO_ORDERDATE            Date,
    LO_ORDERPRIORITY        LowCardinality(String),
    LO_SHIPPRIORITY         UInt8,
    LO_QUANTITY             UInt8,
    LO_EXTENDEDPRICE        UInt32,
    LO_ORDTOTALPRICE        UInt32,
    LO_DISCOUNT             UInt8,
    LO_REVENUE              UInt32,
    LO_SUPPLYCOST           UInt32,
    LO_TAX                  UInt8,
    LO_COMMITDATE           Date,
    LO_SHIPMODE             LowCardinality(String)
)
ENGINE = MergeTree PARTITION BY toYear(LO_ORDERDATE) ORDER BY (LO_ORDERDATE, LO_ORDERKEY);

CREATE TABLE part
(
        P_PARTKEY       UInt32,
        P_NAME          String,
        P_MFGR          LowCardinality(String),
        P_CATEGORY      LowCardinality(String),
        P_BRAND         LowCardinality(String),
        P_COLOR         LowCardinality(String),
        P_TYPE          LowCardinality(String),
        P_SIZE          UInt8,
        P_CONTAINER     LowCardinality(String)
)
ENGINE = MergeTree ORDER BY P_PARTKEY;

CREATE TABLE supplier
(
        S_SUPPKEY       UInt32,
        S_NAME          String,
        S_ADDRESS       String,
        S_CITY          LowCardinality(String),
        S_NATION        LowCardinality(String),
        S_REGION        LowCardinality(String),
        S_PHONE         String
)
ENGINE = MergeTree ORDER BY S_SUPPKEY;

star schema转换为flat schema

SET max_memory_usage = 20000000000;

CREATE TABLE lineorder_flat
ENGINE = MergeTree
PARTITION BY toYear(LO_ORDERDATE)
ORDER BY (LO_ORDERDATE, LO_ORDERKEY) AS
SELECT
    l.LO_ORDERKEY AS LO_ORDERKEY,
    l.LO_LINENUMBER AS LO_LINENUMBER,
    l.LO_CUSTKEY AS LO_CUSTKEY,
    l.LO_PARTKEY AS LO_PARTKEY,
    l.LO_SUPPKEY AS LO_SUPPKEY,
    l.LO_ORDERDATE AS LO_ORDERDATE,
    l.LO_ORDERPRIORITY AS LO_ORDERPRIORITY,
    l.LO_SHIPPRIORITY AS LO_SHIPPRIORITY,
    l.LO_QUANTITY AS LO_QUANTITY,
    l.LO_EXTENDEDPRICE AS LO_EXTENDEDPRICE,
    l.LO_ORDTOTALPRICE AS LO_ORDTOTALPRICE,
    l.LO_DISCOUNT AS LO_DISCOUNT,
    l.LO_REVENUE AS LO_REVENUE,
    l.LO_SUPPLYCOST AS LO_SUPPLYCOST,
    l.LO_TAX AS LO_TAX,
    l.LO_COMMITDATE AS LO_COMMITDATE,
    l.LO_SHIPMODE AS LO_SHIPMODE,
    c.C_NAME AS C_NAME,
    c.C_ADDRESS AS C_ADDRESS,
    c.C_CITY AS C_CITY,
    c.C_NATION AS C_NATION,
    c.C_REGION AS C_REGION,
    c.C_PHONE AS C_PHONE,
    c.C_MKTSEGMENT AS C_MKTSEGMENT,
    s.S_NAME AS S_NAME,
    s.S_ADDRESS AS S_ADDRESS,
    s.S_CITY AS S_CITY,
    s.S_NATION AS S_NATION,
    s.S_REGION AS S_REGION,
    s.S_PHONE AS S_PHONE,
    p.P_NAME AS P_NAME,
    p.P_MFGR AS P_MFGR,
    p.P_CATEGORY AS P_CATEGORY,
    p.P_BRAND AS P_BRAND,
    p.P_COLOR AS P_COLOR,
    p.P_TYPE AS P_TYPE,
    p.P_SIZE AS P_SIZE,
    p.P_CONTAINER AS P_CONTAINER
FROM lineorder AS l
INNER JOIN customer AS c ON c.C_CUSTKEY = l.LO_CUSTKEY
INNER JOIN supplier AS s ON s.S_SUPPKEY = l.LO_SUPPKEY
INNER JOIN part AS p ON p.P_PARTKEY = l.LO_PARTKEY;

Q1.2

SELECT sum(LO_EXTENDEDPRICE * LO_DISCOUNT) AS revenue
FROM lineorder_flat
WHERE toYYYYMM(LO_ORDERDATE) = 199401 AND LO_DISCOUNT BETWEEN 4 AND 6 AND LO_QUANTITY BETWEEN 26 AND 35;

Q2.1

SELECT
    sum(LO_REVENUE),
    toYear(LO_ORDERDATE) AS year,
    P_BRAND
FROM lineorder_flat
WHERE P_CATEGORY = 'MFGR#12' AND S_REGION = 'AMERICA'
GROUP BY
    year,
    P_BRAND
ORDER BY
    year,
    P_BRAND;

Q2.3

SELECT
    sum(LO_REVENUE),
    toYear(LO_ORDERDATE) AS year,
    P_BRAND
FROM lineorder_flat
WHERE P_BRAND = 'MFGR#2239' AND S_REGION = 'EUROPE'
GROUP BY
    year,
    P_BRAND
ORDER BY
    year,
    P_BRAND;

Q3.2

SELECT
    C_CITY,
    S_CITY,
    toYear(LO_ORDERDATE) AS year,
    sum(LO_REVENUE) AS revenue
FROM lineorder_flat
WHERE C_NATION = 'UNITED STATES' AND S_NATION = 'UNITED STATES' AND year >= 1992 AND year <= 1997
GROUP BY
    C_CITY,
    S_CITY,
    year
ORDER BY
    year ASC,
    revenue DESC;

Q3.4

SELECT
    C_CITY,
    S_CITY,
    toYear(LO_ORDERDATE) AS year,
    sum(LO_REVENUE) AS revenue
FROM lineorder_flat
WHERE (C_CITY = 'UNITED KI1' OR C_CITY = 'UNITED KI5') AND (S_CITY = 'UNITED KI1' OR S_CITY = 'UNITED KI5') AND toYYYYMM(LO_ORDERDATE) = 199712
GROUP BY
    C_CITY,
    S_CITY,
    year
ORDER BY
    year ASC,
    revenue DESC;

Q4.2

SELECT
    toYear(LO_ORDERDATE) AS year,
    S_NATION,
    P_CATEGORY,
    sum(LO_REVENUE - LO_SUPPLYCOST) AS profit
FROM lineorder_flat
WHERE C_REGION = 'AMERICA' AND S_REGION = 'AMERICA' AND (year = 1997 OR year = 1998) AND (P_MFGR = 'MFGR#1' OR P_MFGR = 'MFGR#2')
GROUP BY
    year,
    S_NATION,
    P_CATEGORY
ORDER BY
    year ASC,
    S_NATION ASC,
    P_CATEGORY ASC;

加载数据:

$ for i in {2007..2016}; do for j in {01..12}; do echo $i-$j >&2; curl -sSL "http://dumps.wikimedia.org/other/pagecounts-raw/$i/$i-$j/" | grep -oE 'pagecounts-[0-9]+-[0-9]+\.gz'; done; done | sort | uniq | tee links.txt
$ cat links.txt | while read link; do wget http://dumps.wikimedia.org/other/pagecounts-raw/$(echo $link | sed -r 's/pagecounts-([0-9]{4})([0-9]{2})[0-9]{2}-[0-9]+\.gz/\1/')/$(echo $link | sed -r 's/pagecounts-([0-9]{4})([0-9]{2})[0-9]{2}-[0-9]+\.gz/\1-\2/')/$link; done
$ ls -1 /opt/wikistat/ | grep gz | while read i; do echo $i; gzip -cd /opt/wikistat/$i | ./wikistat-loader --time="$(echo -n $i | sed -r 's/pagecounts-([0-9]{4})([0-9]{2})([0-9]{2})-([0-9]{2})([0-9]{2})([0-9]{2})\.gz/\1-\2-\3 \4-00-00/')" | clickhouse-client --query="INSERT INTO wikistat FORMAT TabSeparated"; done

Terabyte of Click Logs from Criteo

可以从 http://labs.criteo.com/downloads/download-terabyte-click-logs/ 上下载数据

创建原始数据对应的表结构:

CREATE TABLE criteo_log (date Date, clicked UInt8, int1 Int32, int2 Int32, int3 Int32, int4 Int32, int5 Int32, int6 Int32, int7 Int32, int8 Int32, int9 Int32, int10 Int32, int11 Int32, int12 Int32, int13 Int32, cat1 String, cat2 String, cat3 String, cat4 String, cat5 String, cat6 String, cat7 String, cat8 String, cat9 String, cat10 String, cat11 String, cat12 String, cat13 String, cat14 String, cat15 String, cat16 String, cat17 String, cat18 String, cat19 String, cat20 String, cat21 String, cat22 String, cat23 String, cat24 String, cat25 String, cat26 String) ENGINE = Log

创建转换后的数据对应的表结构:

CREATE TABLE criteo
(
    date Date,
    clicked UInt8,
    int1 Int32,
    int2 Int32,
    int3 Int32,
    int4 Int32,
    int5 Int32,
    int6 Int32,
    int7 Int32,
    int8 Int32,
    int9 Int32,
    int10 Int32,
    int11 Int32,
    int12 Int32,
    int13 Int32,
    icat1 UInt32,
    icat2 UInt32,
    icat3 UInt32,
    icat4 UInt32,
    icat5 UInt32,
    icat6 UInt32,
    icat7 UInt32,
    icat8 UInt32,
    icat9 UInt32,
    icat10 UInt32,
    icat11 UInt32,
    icat12 UInt32,
    icat13 UInt32,
    icat14 UInt32,
    icat15 UInt32,
    icat16 UInt32,
    icat17 UInt32,
    icat18 UInt32,
    icat19 UInt32,
    icat20 UInt32,
    icat21 UInt32,
    icat22 UInt32,
    icat23 UInt32,
    icat24 UInt32,
    icat25 UInt32,
    icat26 UInt32
) ENGINE = MergeTree(date, intHash32(icat1), (date, intHash32(icat1)), 8192)

在ClickHouse运行如下查询:

CREATE TABLE rankings_tiny
(
    pageURL String,
    pageRank UInt32,
    avgDuration UInt32
) ENGINE = Log;

CREATE TABLE uservisits_tiny
(
    sourceIP String,
    destinationURL String,
    visitDate Date,
    adRevenue Float32,
    UserAgent String,
    cCode FixedString(3),
    lCode FixedString(6),
    searchWord String,
    duration UInt32
) ENGINE = MergeTree(visitDate, visitDate, 8192);

CREATE TABLE rankings_1node
(
    pageURL String,
    pageRank UInt32,
    avgDuration UInt32
) ENGINE = Log;

CREATE TABLE uservisits_1node
(
    sourceIP String,
    destinationURL String,
    visitDate Date,
    adRevenue Float32,
    UserAgent String,
    cCode FixedString(3),
    lCode FixedString(6),
    searchWord String,
    duration UInt32
) ENGINE = MergeTree(visitDate, visitDate, 8192);

CREATE TABLE rankings_5nodes_on_single
(
    pageURL String,
    pageRank UInt32,
    avgDuration UInt32
) ENGINE = Log;

CREATE TABLE uservisits_5nodes_on_single
(
    sourceIP String,
    destinationURL String,
    visitDate Date,
    adRevenue Float32,
    UserAgent String,
    cCode FixedString(3),
    lCode FixedString(6),
    searchWord String,
    duration UInt32
) ENGINE = MergeTree(visitDate, visitDate, 8192);

简单的查询示例:

SELECT pageURL, pageRank FROM rankings_1node WHERE pageRank > 1000

SELECT substring(sourceIP, 1, 8), sum(adRevenue) FROM uservisits_1node GROUP BY substring(sourceIP, 1, 8)

SELECT
    sourceIP,
    sum(adRevenue) AS totalRevenue,
    avg(pageRank) AS pageRank
FROM rankings_1node ALL INNER JOIN
(
    SELECT
        sourceIP,
        destinationURL AS pageURL,
        adRevenue
    FROM uservisits_1node
    WHERE (visitDate > '1980-01-01') AND (visitDate < '1980-04-01')
) USING pageURL
GROUP BY sourceIP
ORDER BY totalRevenue DESC
LIMIT 1

纽约出租车数据

纽约市出租车数据有以下两个方式获取:

  • 从原始数据导入
  • 下载处理好的数据

怎样导入原始数据?

可以参考 https://github.com/toddwschneider/nyc-taxi-data 和 http://tech.marksblogg.com/billion-nyc-taxi-rides-redshift.html 中的关于数据集结构描述与数据下载指令说明。

数据集包含227GB的CSV文件。在1Gbig的带宽下,下载大约需要一个小时这大约需要一个小时的下载时间(从s3.amazonaws.com并行下载时间至少可以缩减一半)。 下载时注意损坏的文件。可以检查文件大小并重新下载损坏的文件。

有些文件中包含一些无效的行,您可以使用如下语句修复他们:

sed -E '/(.*,){18,}/d' data/yellow_tripdata_2010-02.csv > data/yellow_tripdata_2010-02.csv_
sed -E '/(.*,){18,}/d' data/yellow_tripdata_2010-03.csv > data/yellow_tripdata_2010-03.csv_
mv data/yellow_tripdata_2010-02.csv_ data/yellow_tripdata_2010-02.csv
mv data/yellow_tripdata_2010-03.csv_ data/yellow_tripdata_2010-03.csv

(根据Mark Litwintschik的系列博客报道数据略多余11亿行)

PostgreSQL处理这些数据大概需要370GB的磁盘空间。

从PostgreSQL中导出数据:

COPY
(
SELECT trips.id,
trips.vendor_id,
trips.pickup_datetime,
trips.dropoff_datetime,
trips.store_and_fwd_flag,
trips.rate_code_id,
trips.pickup_longitude,
trips.pickup_latitude,
trips.dropoff_longitude,
trips.dropoff_latitude,
trips.passenger_count,
trips.trip_distance,
trips.fare_amount,
trips.extra,
trips.mta_tax,
trips.tip_amount,
trips.tolls_amount,
trips.ehail_fee,
trips.improvement_surcharge,
trips.total_amount,
trips.payment_type,
trips.trip_type,
trips.pickup,
trips.dropoff,

cab_types.type cab_type,

weather.precipitation_tenths_of_mm rain,
weather.snow_depth_mm,
weather.snowfall_mm,
weather.max_temperature_tenths_degrees_celsius max_temp,
weather.min_temperature_tenths_degrees_celsius min_temp,
weather.average_wind_speed_tenths_of_meters_per_second wind,

pick_up.gid pickup_nyct2010_gid,
pick_up.ctlabel pickup_ctlabel,
pick_up.borocode pickup_borocode,
pick_up.boroname pickup_boroname,
pick_up.ct2010 pickup_ct2010,
pick_up.boroct2010 pickup_boroct2010,
pick_up.cdeligibil pickup_cdeligibil,
pick_up.ntacode pickup_ntacode,
pick_up.ntaname pickup_ntaname,
pick_up.puma pickup_puma,

drop_off.gid dropoff_nyct2010_gid,
drop_off.ctlabel dropoff_ctlabel,
drop_off.borocode dropoff_borocode,
drop_off.boroname dropoff_boroname,
drop_off.ct2010 dropoff_ct2010,
drop_off.boroct2010 dropoff_boroct2010,
drop_off.cdeligibil dropoff_cdeligibil,
drop_off.ntacode dropoff_ntacode,
drop_off.ntaname dropoff_ntaname,
drop_off.puma dropoff_puma
FROM trips
LEFT JOIN cab_types
ON trips.cab_type_id = cab_types.id
LEFT JOIN central_park_weather_observations_raw weather
ON weather.date = trips.pickup_datetime::date
LEFT JOIN nyct2010 pick_up
ON pick_up.gid = trips.pickup_nyct2010_gid
LEFT JOIN nyct2010 drop_off
ON drop_off.gid = trips.dropoff_nyct2010_gid
) TO '/opt/milovidov/nyc-taxi-data/trips.tsv';

接下来,需要将字段转换为更正确的数据类型,并且在可能的情况下,消除NULL。

$ time clickhouse-client --query="INSERT INTO trips FORMAT TabSeparated" < trips.tsv

real 75m56.214s

这需要3030秒,速度约为每秒428,000行。 要加快速度,可以使用Log引擎替换MergeTree引擎来创建表。 在这种情况下,下载速度超过200秒。

这个表需要使用126GB的磁盘空间。

SELECT formatReadableSize(sum(bytes)) FROM system.parts WHERE table = 'trips_mergetree' AND active

除此之外,你还可以在MergeTree上运行OPTIMIZE查询来进行优化。但这不是必须的,因为即使在没有进行优化的情况下它的表现依然是很好的。

下载预处理好的分区数据?

$ curl -O https://datasets.clickhouse.com/trips_mergetree/partitions/trips_mergetree.tar
$ tar xvf trips_mergetree.tar -C /var/lib/clickhouse # path to ClickHouse data directory
$ # check permissions of unpacked data, fix if required
$ sudo service clickhouse-server restart
$ clickhouse-client --query "select count(*) from datasets.trips_mergetree"

0.490秒

Q2:

SELECT passenger_count, avg(total_amount) FROM trips_mergetree GROUP BY passenger_count

2.104秒

Q4:

SELECT passenger_count, toYear(pickup_date) AS year, round(trip_distance) AS distance, count(*)
FROM trips_mergetree
GROUP BY passenger_count, year, distance
ORDER BY year, count(*) DESC

在之前的服务器中运行:

CREATE TABLE trips_mergetree_x3 AS trips_mergetree_third ENGINE = Distributed(perftest, default, trips_mergetree_third, rand())

这个查询需要运行2454秒。

在三台服务器集群中运行的结果:

Q1: 0.212秒. Q2:0.438秒。 Q3:0.733秒。 Q4: 1.241秒.

这并不奇怪,因为查询是线性扩展的。

我们同时在140台服务器的集群中运行的结果:

Q1:0.028秒。 Q2:0.043秒。 Q3:0.051秒。 Q4:0.072秒。

在这种情况下,查询处理时间首先由网络延迟确定。

总结?

服务器Q1Q2Q3Q4
1 0.490 1.224 2.104 3.593
3 0.212 0.438 0.733 1.241
140 0.028 0.043 0.051 0.072

OnTime

航班飞行数据有以下两个方式获取:

  • 从原始数据导入
  • 下载预处理好的数据

从原始数据导入?

下载数据:

wget --no-check-certificate --continue https://transtats.bts.gov/PREZIP/On_Time_Reporting_Carrier_On_Time_Performance_1987_present_{1987..2021}_{1..12}.zip

加载数据:

ls -1 *.zip | xargs -I{} -P $(nproc) bash -c "echo {}; unzip -cq {} '*.csv' | sed 's/\.00//g' | clickhouse-client --input_format_with_names_use_header=0 --query='INSERT INTO ontime FORMAT CSVWithNames'"

!!! info "信息" 如果要运行下面的SQL查询,必须使用完整的表名,datasets.ontime

查询:?

Q0.

SELECT avg(c1)
FROM
(
SELECT Year, Month, count(*) AS c1
FROM ontime
GROUP BY Year, Month
);

Q2. 查询从2000年到2008年每周延误超过10分钟的航班数。

SELECT DayOfWeek, count(*) AS c
FROM ontime
WHERE DepDelay>10 AND Year>=2000 AND Year<=2008
GROUP BY DayOfWeek
ORDER BY c DESC;

Q4. 查询2007年各航空公司延误超过10分钟以上的次数

SELECT IATA_CODE_Reporting_Airline AS Carrier, count(*)
FROM ontime
WHERE DepDelay>10 AND Year=2007
GROUP BY Carrier
ORDER BY count(*) DESC;

更好的查询版本:

SELECT IATA_CODE_Reporting_Airline AS Carrier, avg(DepDelay>10)*100 AS c3
FROM ontime
WHERE Year=2007
GROUP BY Carrier
ORDER BY c3 DESC

更好的查询版本:

SELECT IATA_CODE_Reporting_Airline AS Carrier, avg(DepDelay>10)*100 AS c3
FROM ontime
WHERE Year>=2000 AND Year<=2008
GROUP BY Carrier
ORDER BY c3 DESC;

更好的查询版本:

SELECT Year, avg(DepDelay>10)*100
FROM ontime
GROUP BY Year
ORDER BY Year;

Q9.

SELECT Year, count(*) AS c1
FROM ontime
GROUP BY Year;

Bonus:

SELECT avg(cnt)
FROM
(
SELECT Year,Month,count(*) AS cnt
FROM ontime
WHERE DepDel15=1
GROUP BY Year,Month
);

SELECT avg(c1) FROM
(
SELECT Year,Month,count(*) AS c1
FROM ontime
GROUP BY Year,Month
);

SELECT DestCityName, uniqExact(OriginCityName) AS u
FROM ontime
GROUP BY DestCityName
ORDER BY u DESC
LIMIT 10;

SELECT OriginCityName, DestCityName, count() AS c
FROM ontime
GROUP BY OriginCityName, DestCityName
ORDER BY c DESC
LIMIT 10;

SELECT OriginCityName, count() AS c
FROM ontime
GROUP BY OriginCityName
ORDER BY c DESC
LIMIT 10;

Unpack the data:

xz -v -d mgbench{1..3}.csv.xz

Insert data:

clickhouse-client --query "INSERT INTO mgbench.logs1 FORMAT CSVWithNames" < mgbench1.csv
clickhouse-client --query "INSERT INTO mgbench.logs2 FORMAT CSVWithNames" < mgbench2.csv
clickhouse-client --query "INSERT INTO mgbench.logs3 FORMAT CSVWithNames" < mgbench3.csv
  1. Decompress it with the following command:
xz -d cell_towers.csv.xz
  1. Insert the dataset:
clickhouse-client --query "INSERT INTO cell_towers FORMAT CSVWithNames" < cell_towers.csv
  1. Cell towers by mobile country code (MCC):
SELECT mcc, count() FROM cell_towers GROUP BY mcc ORDER BY count() DESC LIMIT 10

┌─mcc─┬─count()─┐
│ 310 │ 5024650 │
│ 262 │ 2622423 │
│ 250 │ 1953176 │
│ 208 │ 1891187 │
│ 724 │ 1836150 │
│ 404 │ 1729151 │
│ 234 │ 1618924 │
│ 510 │ 1353998 │
│ 440 │ 1343355 │
│ 311 │ 1332798 │
└─────┴─────────┘

10 rows in set. Elapsed: 0.019 sec. Processed 43.28 million rows, 86.55 MB (2.33 billion rows/s., 4.65 GB/s.)
  1. This is a rough shape of Moscow (without "new Moscow"):
INSERT INTO moscow VALUES ([(37.84172564285271, 55.78000432402266), (37.8381207618713, 55.775874525970494), (37.83979446823122, 55.775626746008065), (37.84243326983639, 55.77446586811748), (37.84262672750849, 55.771974101091104), (37.84153238623039, 55.77114545193181), (37.841124690460184, 55.76722010265554), (37.84239076983644, 55.76654891107098), (37.842283558197025, 55.76258709833121), (37.8421759312134, 55.758073999993734), (37.84198330422974, 55.75381499999371), (37.8416827275085, 55.749277102484484), (37.84157576190186, 55.74794544108413), (37.83897929098507, 55.74525257875241), (37.83739676451868, 55.74404373042019), (37.838732481460525, 55.74298009816793), (37.841183997352545, 55.743060321833575), (37.84097476190185, 55.73938799999373), (37.84048155819702, 55.73570799999372), (37.840095812164286, 55.73228210777237), (37.83983814285274, 55.73080491981639), (37.83846476321406, 55.729799917464675), (37.83835745269769, 55.72919751082619), (37.838636380279524, 55.72859509486539), (37.8395161005249, 55.727705075632784), (37.83897964285276, 55.722727886185154), (37.83862557539366, 55.72034817326636), (37.83559735744853, 55.71944437307499), (37.835370708803126, 55.71831419154461), (37.83738169402022, 55.71765218986692), (37.83823396494291, 55.71691750159089), (37.838056931213345, 55.71547311301385), (37.836812846557606, 55.71221445615604), (37.83522525396725, 55.709331054395555), (37.83269301586908, 55.70953687463627), (37.829667367706236, 55.70903403789297), (37.83311126588435, 55.70552351822608), (37.83058993121339, 55.70041317726053), (37.82983872750851, 55.69883771404813), (37.82934501586913, 55.69718947487017), (37.828926414016685, 55.69504441658371), (37.82876530422971, 55.69287499999378), (37.82894754100031, 55.690759754047335), (37.827697554878185, 55.68951421135665), (37.82447346292115, 55.68965045405069), (37.83136543914793, 55.68322046195302), (37.833554015869154, 55.67814012759211), (37.83544184655761, 55.67295011628339), (37.837480388885474, 55.6672498719639), (37.838960677246064, 55.66316274139358), (37.83926093121332, 55.66046999999383), (37.839025050262435, 55.65869897264431), (37.83670784390257, 55.65794084879904), (37.835656529083245, 55.65694309303843), (37.83704060449217, 55.65689306460552), (37.83696819873806, 55.65550363526252), (37.83760389616388, 55.65487847246661), (37.83687972750851, 55.65356745541324), (37.83515216004943, 55.65155951234079), (37.83312418518067, 55.64979413590619), (37.82801726983639, 55.64640836412121), (37.820614174591, 55.64164525405531), (37.818908190475426, 55.6421883258084), (37.81717543386075, 55.64112490388471), (37.81690987037274, 55.63916106913107), (37.815099354492155, 55.637925371757085), (37.808769150787356, 55.633798276884455), (37.80100123544311, 55.62873670012244), (37.79598013491824, 55.62554336109055), (37.78634567724606, 55.62033499605651), (37.78334147619623, 55.618768681480326), (37.77746201055901, 55.619855533402706), (37.77527329626457, 55.61909966711279), (37.77801986242668, 55.618770300976294), (37.778212973541216, 55.617257701952106), (37.77784818518065, 55.61574504433011), (37.77016867724609, 55.61148576294007), (37.760191219573976, 55.60599579539028), (37.75338926983641, 55.60227892751446), (37.746329965606634, 55.59920577639331), (37.73939925396728, 55.59631430313617), (37.73273665739439, 55.5935318803559), (37.7299954450912, 55.59350760316188), (37.7268679946899, 55.59469840523759), (37.72626726983634, 55.59229549697373), (37.7262673598022, 55.59081598950582), (37.71897193121335, 55.5877595845419), (37.70871550793456, 55.58393177431724), (37.700497489410374, 55.580917323756644), (37.69204305026244, 55.57778089778455), (37.68544477378839, 55.57815154690915), (37.68391050793454, 55.57472945079756), (37.678803592590306, 55.57328235936491), (37.6743402539673, 55.57255251445782), (37.66813862698363, 55.57216388774464), (37.617927457672096, 55.57505691895805), (37.60443099999999, 55.5757737568051), (37.599683515869145, 55.57749105910326), (37.59754177842709, 55.57796291823627), (37.59625834786988, 55.57906686095235), (37.59501783265684, 55.57746616444403), (37.593090671936025, 55.57671634534502), (37.587018007904, 55.577944600233785), (37.578692203704804, 55.57982895000019), (37.57327546607398, 55.58116294118248), (37.57385012109279, 55.581550362779), (37.57399562266922, 55.5820107079112), (37.5735356072979, 55.58226289171689), (37.57290393054962, 55.582393529795155), (37.57037722355653, 55.581919415056234), (37.5592298306885, 55.584471614867844), (37.54189249206543, 55.58867650795186), (37.5297256269836, 55.59158133551745), (37.517837865081766, 55.59443656218868), (37.51200186508174, 55.59635625174229), (37.506808949737554, 55.59907823904434), (37.49820432275389, 55.6062944994944), (37.494406071441674, 55.60967103463367), (37.494760001358024, 55.61066689753365), (37.49397137107085, 55.61220931698269), (37.49016528606031, 55.613417718449064), (37.48773249206542, 55.61530616333343), (37.47921386508177, 55.622640129112334), (37.470652153442394, 55.62993723476164), (37.46273446298218, 55.6368075123157), (37.46350692265317, 55.64068225239439), (37.46050283203121, 55.640794546982576), (37.457627470916734, 55.64118904154646), (37.450718034393326, 55.64690488145138), (37.44239252645875, 55.65397824729769), (37.434587576721185, 55.66053543155961), (37.43582144975277, 55.661693766520735), (37.43576786245721, 55.662755031737014), (37.430982915344174, 55.664610641628116), (37.428547447097685, 55.66778515273695), (37.42945134592044, 55.668633314343566), (37.42859571562949, 55.66948145750025), (37.4262836402282, 55.670813882451405), (37.418709037048295, 55.6811141674414), (37.41922139651101, 55.68235377885389), (37.419218771842885, 55.68359335082235), (37.417196501327446, 55.684375235224735), (37.41607020370478, 55.68540557585352), (37.415640857147146, 55.68686637150793), (37.414632153442334, 55.68903015131686), (37.413344899475064, 55.690896881757396), (37.41171432275391, 55.69264232162232), (37.40948282275393, 55.69455101638112), (37.40703674603271, 55.69638690385348), (37.39607169577025, 55.70451821283731), (37.38952706878662, 55.70942491932811), (37.387778313491815, 55.71149057784176), (37.39049275399779, 55.71419814298992), (37.385557272491454, 55.7155489617061), (37.38388335714726, 55.71849856042102), (37.378368238098155, 55.7292763261685), (37.37763597123337, 55.730845879211614), (37.37890062088197, 55.73167906388319), (37.37750451918789, 55.734703664681774), (37.375610832015965, 55.734851959522246), (37.3723813571472, 55.74105626086403), (37.37014935714723, 55.746115620904355), (37.36944173016362, 55.750883999993725), (37.36975304365541, 55.76335905525834), (37.37244070571134, 55.76432079697595), (37.3724259757175, 55.76636979670426), (37.369922155757884, 55.76735417953104), (37.369892695770275, 55.76823419316575), (37.370214730163575, 55.782312184391266), (37.370493611114505, 55.78436801120489), (37.37120164550783, 55.78596427165359), (37.37284851456452, 55.7874378183096), (37.37608325135799, 55.7886695054807), (37.3764587460632, 55.78947647305964), (37.37530000265506, 55.79146512926804), (37.38235915344241, 55.79899647809345), (37.384344043655396, 55.80113596939471), (37.38594269577028, 55.80322699999366), (37.38711208598329, 55.804919036911976), (37.3880239841309, 55.806610999993666), (37.38928977249147, 55.81001864976979), (37.39038389947512, 55.81348641242801), (37.39235781481933, 55.81983538336746), (37.393709457672124, 55.82417822811877), (37.394685720901464, 55.82792275755836), (37.39557615344238, 55.830447148154136), (37.39844478226658, 55.83167107969975), (37.40019761214057, 55.83151823557964), (37.400398790382326, 55.83264967594742), (37.39659544313046, 55.83322180909622), (37.39667059524539, 55.83402792148566), (37.39682089947515, 55.83638877400216), (37.39643489154053, 55.83861656112751), (37.3955338994751, 55.84072348043264), (37.392680272491454, 55.84502158126453), (37.39241188227847, 55.84659117913199), (37.392529730163616, 55.84816071336481), (37.39486835714723, 55.85288092980303), (37.39873052645878, 55.859893456073635), (37.40272161111449, 55.86441833633205), (37.40697072750854, 55.867579567544375), (37.410007082016016, 55.868369880337), (37.4120992989502, 55.86920843741314), (37.412668021163924, 55.87055369615854), (37.41482461111453, 55.87170587948249), (37.41862266137694, 55.873183961039565), (37.42413732540892, 55.874879126654704), (37.4312182698669, 55.875614937236705), (37.43111093783558, 55.8762723478417), (37.43332105622856, 55.87706546369396), (37.43385747619623, 55.87790681284802), (37.441303050262405, 55.88027084462084), (37.44747234260555, 55.87942070143253), (37.44716141796871, 55.88072960917233), (37.44769797085568, 55.88121221323979), (37.45204320500181, 55.882080694420715), (37.45673176190186, 55.882346110794586), (37.463383999999984, 55.88252729504517), (37.46682797486874, 55.88294937719063), (37.470014457672086, 55.88361266759345), (37.47751410450743, 55.88546991372396), (37.47860317658232, 55.88534929207307), (37.48165826025772, 55.882563306475106), (37.48316434442331, 55.8815803226785), (37.483831555817645, 55.882427612793315), (37.483182967125686, 55.88372791409729), (37.483092277908824, 55.88495581062434), (37.4855716508179, 55.8875561994203), (37.486440636245746, 55.887827444039566), (37.49014203439328, 55.88897899871799), (37.493210285705544, 55.890208937135604), (37.497512451065035, 55.891342397444696), (37.49780744510645, 55.89174030252967), (37.49940333499519, 55.89239745507079), (37.50018383334346, 55.89339220941865), (37.52421672750851, 55.903869074155224), (37.52977457672118, 55.90564076517974), (37.53503220370484, 55.90661661218259), (37.54042858064267, 55.90714113744566), (37.54320461007303, 55.905645048442985), (37.545686966066306, 55.906608607018505), (37.54743976120755, 55.90788552162358), (37.55796999999999, 55.90901557907218), (37.572711542327866, 55.91059395704873), (37.57942799999998, 55.91073854155573), (37.58502865872187, 55.91009969268444), (37.58739968913264, 55.90794809960554), (37.59131567193598, 55.908713267595054), (37.612687423278814, 55.902866854295375), (37.62348079629517, 55.90041967242986), (37.635797880950896, 55.898141151686396), (37.649487626983664, 55.89639275532968), (37.65619302513125, 55.89572360207488), (37.66294133862307, 55.895295577183965), (37.66874564418033, 55.89505457604897), (37.67375601586915, 55.89254677027454), (37.67744661901856, 55.8947775867987), (37.688347, 55.89450045676125), (37.69480554232789, 55.89422926332761), (37.70107096560668, 55.89322256101114), (37.705962965606716, 55.891763491662616), (37.711885134918205, 55.889110234998974), (37.71682005026245, 55.886577568759876), (37.7199315476074, 55.88458159806678), (37.72234560316464, 55.882281005794134), (37.72364385977171, 55.8809452036196), (37.725371142837474, 55.8809722706006), (37.727870902099546, 55.88037213862385), (37.73394330422971, 55.877941504088696), (37.745339592590376, 55.87208120378722), (37.75525267724611, 55.86703807949492), (37.76919976190188, 55.859821640197474), (37.827835219574, 55.82962968399116), (37.83341438888553, 55.82575289922351), (37.83652584655761, 55.82188784027888), (37.83809213491821, 55.81612575504693), (37.83605359521481, 55.81460347077685), (37.83632178569025, 55.81276696067908), (37.838623105812026, 55.811486181656385), (37.83912198147584, 55.807329380532785), (37.839079078033414, 55.80510270463816), (37.83965844708251, 55.79940712529036), (37.840581150787344, 55.79131399999368), (37.84172564285271, 55.78000432402266)]);

The data is also available for interactive queries in the Playground, example.

Although you cannot create temporary tables there.

New York Public Library "What's on the Menu?" Dataset

The dataset is created by the New York Public Library. It contains historical data on the menus of hotels, restaurants and cafes with the dishes along with their prices.

Source: http://menus.nypl.org/data The data is in public domain.

The data is from library's archive and it may be incomplete and difficult for statistical analysis. Nevertheless it is also very yummy. The size is just 1.3 million records about dishes in the menus — it's a very small data volume for ClickHouse, but it's still a good example.

Download the Dataset?

Run the command:

wget https://s3.amazonaws.com/menusdata.nypl.org/gzips/2021_08_01_07_01_17_data.tgz

Uncompressed size is about 150 MB.

The data is normalized consisted of four tables:

  • Menu — Information about menus: the name of the restaurant, the date when menu was seen, etc.
  • Dish — Information about dishes: the name of the dish along with some characteristic.
  • MenuPage — Information about the pages in the menus, because every page belongs to some menu.
  • MenuItem — An item of the menu. A dish along with its price on some menu page: links to dish and menu page.

Create the Tables?

We use Decimal data type to store prices.

CREATE TABLE dish
(
id UInt32,
name String,
description String,
menus_appeared UInt32,
times_appeared Int32,
first_appeared UInt16,
last_appeared UInt16,
lowest_price Decimal64(3),
highest_price Decimal64(3)
) ENGINE = MergeTree ORDER BY id;

CREATE TABLE menu
(
id UInt32,
name String,
sponsor String,
event String,
venue String,
place String,
physical_description String,
occasion String,
notes String,
call_number String,
keywords String,
language String,
date String,
location String,
location_type String,
currency String,
currency_symbol String,
status String,
page_count UInt16,
dish_count UInt16
) ENGINE = MergeTree ORDER BY id;

CREATE TABLE menu_page
(
id UInt32,
menu_id UInt32,
page_number UInt16,
image_id String,
full_height UInt16,
full_width UInt16,
uuid UUID
) ENGINE = MergeTree ORDER BY id;

CREATE TABLE menu_item
(
id UInt32,
menu_page_id UInt32,
price Decimal64(3),
high_price Decimal64(3),
dish_id UInt32,
created_at DateTime,
updated_at DateTime,
xpos Float64,
ypos Float64
) ENGINE = MergeTree ORDER BY id;

We use CSVWithNames format as the data is represented by CSV with header.

We disable format_csv_allow_single_quotes as only double quotes are used for data fields and single quotes can be inside the values and should not confuse the CSV parser.

We disable input_format_null_as_default as our data does not have NULL. Otherwise ClickHouse will try to parse \N sequences and can be confused with \ in data.

The setting date_time_input_format best_effort allows to parse DateTime fields in wide variety of formats. For example, ISO-8601 without seconds like '2000-01-01 01:02' will be recognized. Without this setting only fixed DateTime format is allowed.

Denormalize the Data?

Data is presented in multiple tables in normalized form. It means you have to perform JOIN if you want to query, e.g. dish names from menu items. For typical analytical tasks it is way more efficient to deal with pre-JOINed data to avoid doing JOIN every time. It is called "denormalized" data.

We will create a table menu_item_denorm where will contain all the data JOINed together:

CREATE TABLE menu_item_denorm
ENGINE = MergeTree ORDER BY (dish_name, created_at)
AS SELECT
price,
high_price,
created_at,
updated_at,
xpos,
ypos,
dish.id AS dish_id,
dish.name AS dish_name,
dish.description AS dish_description,
dish.menus_appeared AS dish_menus_appeared,
dish.times_appeared AS dish_times_appeared,
dish.first_appeared AS dish_first_appeared,
dish.last_appeared AS dish_last_appeared,
dish.lowest_price AS dish_lowest_price,
dish.highest_price AS dish_highest_price,
menu.id AS menu_id,
menu.name AS menu_name,
menu.sponsor AS menu_sponsor,
menu.event AS menu_event,
menu.venue AS menu_venue,
menu.place AS menu_place,
menu.physical_description AS menu_physical_description,
menu.occasion AS menu_occasion,
menu.notes AS menu_notes,
menu.call_number AS menu_call_number,
menu.keywords AS menu_keywords,
menu.language AS menu_language,
menu.date AS menu_date,
menu.location AS menu_location,
menu.location_type AS menu_location_type,
menu.currency AS menu_currency,
menu.currency_symbol AS menu_currency_symbol,
menu.status AS menu_status,
menu.page_count AS menu_page_count,
menu.dish_count AS menu_dish_count
FROM menu_item
JOIN dish ON menu_item.dish_id = dish.id
JOIN menu_page ON menu_item.menu_page_id = menu_page.id
JOIN menu ON menu_page.menu_id = menu.id;

Result:

┌─count()─┐
│ 1329175 │
└─────────┘

Result:

┌────d─┬─count()─┬─round(avg(price), 2)─┬─bar(avg(price), 0, 100, 100)─┐
│ 1850 │ 618 │ 1.5 │ █▍ │
│ 1860 │ 1634 │ 1.29 │ █▎ │
│ 1870 │ 2215 │ 1.36 │ █▎ │
│ 1880 │ 3909 │ 1.01 │ █ │
│ 1890 │ 8837 │ 1.4 │ █▍ │
│ 1900 │ 176292 │ 0.68 │ ▋ │
│ 1910 │ 212196 │ 0.88 │ ▊ │
│ 1920 │ 179590 │ 0.74 │ ▋ │
│ 1930 │ 73707 │ 0.6 │ ▌ │
│ 1940 │ 58795 │ 0.57 │ ▌ │
│ 1950 │ 41407 │ 0.95 │ ▊ │
│ 1960 │ 51179 │ 1.32 │ █▎ │
│ 1970 │ 12914 │ 1.86 │ █▋ │
│ 1980 │ 7268 │ 4.35 │ ████▎ │
│ 1990 │ 11055 │ 6.03 │ ██████ │
│ 2000 │ 2467 │ 11.85 │ ███████████▋ │
│ 2010 │ 597 │ 25.66 │ █████████████████████████▋ │
└──────┴─────────┴──────────────────────┴──────────────────────────────┘

Result:

┌────d─┬─count()─┬─round(avg(price), 2)─┬─bar(avg(price), 0, 50, 100)───────────┐
│ 1880 │ 2 │ 0.42 │ ▋ │
│ 1890 │ 7 │ 0.85 │ █▋ │
│ 1900 │ 399 │ 0.49 │ ▊ │
│ 1910 │ 589 │ 0.68 │ █▎ │
│ 1920 │ 280 │ 0.56 │ █ │
│ 1930 │ 74 │ 0.42 │ ▋ │
│ 1940 │ 119 │ 0.59 │ █▏ │
│ 1950 │ 134 │ 1.09 │ ██▏ │
│ 1960 │ 272 │ 0.92 │ █▋ │
│ 1970 │ 108 │ 1.18 │ ██▎ │
│ 1980 │ 88 │ 2.82 │ █████▋ │
│ 1990 │ 184 │ 3.68 │ ███████▎ │
│ 2000 │ 21 │ 7.14 │ ██████████████▎ │
│ 2010 │ 6 │ 18.42 │ ████████████████████████████████████▋ │
└──────┴─────────┴──────────────────────┴───────────────────────────────────────┘

Result:

┌────d─┬─count()─┬─round(avg(price), 2)─┬─bar(avg(price), 0, 50, 100)─┐
│ 1910 │ 2 │ 0 │ │
│ 1920 │ 1 │ 0.3 │ ▌ │
│ 1940 │ 21 │ 0.42 │ ▋ │
│ 1950 │ 14 │ 0.59 │ █▏ │
│ 1960 │ 113 │ 2.17 │ ████▎ │
│ 1970 │ 37 │ 0.68 │ █▎ │
│ 1980 │ 19 │ 2.55 │ █████ │
│ 1990 │ 86 │ 3.6 │ ███████▏ │
│ 2000 │ 2 │ 3.98 │ ███████▊ │
└──────┴─────────┴──────────────────────┴─────────────────────────────┘

Result:

┌────d─┬─count()─┬─round(avg(price), 2)─┬─bar(avg(price), 0, 50, 100)──────┬─any(dish_name)──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┐
│ 1090 │ 1 │ 0 │ │ Caviar │
│ 1880 │ 3 │ 0 │ │ Caviar │
│ 1890 │ 39 │ 0.59 │ █▏ │ Butter and caviar │
│ 1900 │ 1014 │ 0.34 │ ▋ │ Anchovy Caviar on Toast │
│ 1910 │ 1588 │ 1.35 │ ██▋ │ 1/1 Br?tchen Caviar │
│ 1920 │ 927 │ 1.37 │ ██▋ │ ASTRAKAN CAVIAR │
│ 1930 │ 289 │ 1.91 │ ███▋ │ Astrachan caviar │
│ 1940 │ 201 │ 0.83 │ █▋ │ (SPECIAL) Domestic Caviar Sandwich │
│ 1950 │ 81 │ 2.27 │ ████▌ │ Beluga Caviar │
│ 1960 │ 126 │ 2.21 │ ████▍ │ Beluga Caviar │
│ 1970 │ 105 │ 0.95 │ █▊ │ BELUGA MALOSSOL CAVIAR AMERICAN DRESSING │
│ 1980 │ 12 │ 7.22 │ ██████████████▍ │ Authentic Iranian Beluga Caviar the world's finest black caviar presented in ice garni and a sampling of chilled 100° Russian vodka │
│ 1990 │ 74 │ 14.42 │ ████████████████████████████▋ │ Avocado Salad, Fresh cut avocado with caviare │
│ 2000 │ 3 │ 7.82 │ ███████████████▋ │ Aufgeschlagenes Kartoffelsueppchen mit Forellencaviar │
│ 2010 │ 6 │ 15.58 │ ███████████████████████████████▏ │ "OYSTERS AND PEARLS" "Sabayon" of Pearl Tapioca with Island Creek Oysters and Russian Sevruga Caviar │
└──────┴─────────┴──────────────────────┴──────────────────────────────────┴─────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┘

Download will take about 2 minutes with good internet connection. There are 30 files with total size of 4.3 GB.

Create the Table?

CREATE TABLE opensky
(
callsign String,
number String,
icao24 String,
registration String,
typecode String,
origin String,
destination String,
firstseen DateTime,
lastseen DateTime,
day DateTime,
latitude_1 Float64,
longitude_1 Float64,
altitude_1 Float64,
latitude_2 Float64,
longitude_2 Float64,
altitude_2 Float64
) ENGINE = MergeTree ORDER BY (origin, destination, callsign);
  • Here we pass the list of files (ls -1 flightlist_*.csv.gz) to xargs for parallel processing. xargs -P100 specifies to use up to 100 parallel workers but as we only have 30 files, the number of workers will be only 30.
  • For every file, xargs will run a script with bash -c. The script has substitution in form of {} and the xargs command will substitute the filename to it (we have asked it for xargs with -I{}).
  • The script will decompress the file (gzip -c -d "{}") to standard output (-c parameter) and the output is redirected to clickhouse-client.
  • We also asked to parse DateTime fields with extended parser (--date_time_input_format best_effort) to recognize ISO-8601 format with timezone offsets.

Finally, clickhouse-client will do insertion. It will read input data in CSVWithNames format.

Parallel upload takes 24 seconds.

If you don't like parallel upload, here is sequential variant:

for file in flightlist_*.csv.gz; do gzip -c -d "$file" | clickhouse-client --date_time_input_format best_effort --query "INSERT INTO opensky FORMAT CSVWithNames"; done

Result:

┌──count()─┐
│ 66010819 │
└──────────┘

Result:

┌─formatReadableSize(total_bytes)─┐
│ 2.66 GiB │
└─────────────────────────────────┘

Result:

┌─formatReadableQuantity(divide(sum(geoDistance(longitude_1, latitude_1, longitude_2, latitude_2)), 1000))─┐
│ 68.72 billion │
└──────────────────────────────────────────────────────────────────────────────────────────────────────────┘

Result:

┌─avg(geoDistance(longitude_1, latitude_1, longitude_2, latitude_2))─┐
│ 1041090.6465708319 │
└────────────────────────────────────────────────────────────────────┘

Result:

     ┌─origin─┬─count()─┬─distance─┬─bar────────────────────────────────────┐
1. │ KORD │ 745007 │ 1546108 │ ███████████████▍ │
2. │ KDFW │ 696702 │ 1358721 │ █████████████▌ │
3. │ KATL │ 667286 │ 1169661 │ ███████████▋ │
4. │ KDEN │ 582709 │ 1287742 │ ████████████▊ │
5. │ KLAX │ 581952 │ 2628393 │ ██████████████████████████▎ │
6. │ KLAS │ 447789 │ 1336967 │ █████████████▎ │
7. │ KPHX │ 428558 │ 1345635 │ █████████████▍ │
8. │ KSEA │ 412592 │ 1757317 │ █████████████████▌ │
9. │ KCLT │ 404612 │ 880355 │ ████████▋ │
10. │ VIDP │ 363074 │ 1445052 │ ██████████████▍ │
11. │ EDDF │ 362643 │ 2263960 │ ██████████████████████▋ │
12. │ KSFO │ 361869 │ 2445732 │ ████████████████████████▍ │
13. │ KJFK │ 349232 │ 2996550 │ █████████████████████████████▊ │
14. │ KMSP │ 346010 │ 1287328 │ ████████████▋ │
15. │ LFPG │ 344748 │ 2206203 │ ██████████████████████ │
16. │ EGLL │ 341370 │ 3216593 │ ████████████████████████████████▏ │
17. │ EHAM │ 340272 │ 2116425 │ █████████████████████▏ │
18. │ KEWR │ 337696 │ 1826545 │ ██████████████████▎ │
19. │ KPHL │ 320762 │ 1291761 │ ████████████▊ │
20. │ OMDB │ 308855 │ 2855706 │ ████████████████████████████▌ │
21. │ UUEE │ 307098 │ 1555122 │ ███████████████▌ │
22. │ KBOS │ 304416 │ 1621675 │ ████████████████▏ │
23. │ LEMD │ 291787 │ 1695097 │ ████████████████▊ │
24. │ YSSY │ 272979 │ 1875298 │ ██████████████████▋ │
25. │ KMIA │ 265121 │ 1923542 │ ███████████████████▏ │
26. │ ZGSZ │ 263497 │ 745086 │ ███████▍ │
27. │ EDDM │ 256691 │ 1361453 │ █████████████▌ │
28. │ WMKK │ 254264 │ 1626688 │ ████████████████▎ │
29. │ CYYZ │ 251192 │ 2175026 │ █████████████████████▋ │
30. │ KLGA │ 248699 │ 1106935 │ ███████████ │
31. │ VHHH │ 248473 │ 3457658 │ ██████████████████████████████████▌ │
32. │ RJTT │ 243477 │ 1272744 │ ████████████▋ │
33. │ KBWI │ 241440 │ 1187060 │ ███████████▋ │
34. │ KIAD │ 239558 │ 1683485 │ ████████████████▋ │
35. │ KIAH │ 234202 │ 1538335 │ ███████████████▍ │
36. │ KFLL │ 223447 │ 1464410 │ ██████████████▋ │
37. │ KDAL │ 212055 │ 1082339 │ ██████████▋ │
38. │ KDCA │ 207883 │ 1013359 │ ██████████▏ │
39. │ LIRF │ 207047 │ 1427965 │ ██████████████▎ │
40. │ PANC │ 206007 │ 2525359 │ █████████████████████████▎ │
41. │ LTFJ │ 205415 │ 860470 │ ████████▌ │
42. │ KDTW │ 204020 │ 1106716 │ ███████████ │
43. │ VABB │ 201679 │ 1300865 │ █████████████ │
44. │ OTHH │ 200797 │ 3759544 │ █████████████████████████████████████▌ │
45. │ KMDW │ 200796 │ 1232551 │ ████████████▎ │
46. │ KSAN │ 198003 │ 1495195 │ ██████████████▊ │
47. │ KPDX │ 197760 │ 1269230 │ ████████████▋ │
48. │ SBGR │ 197624 │ 2041697 │ ████████████████████▍ │
49. │ VOBL │ 189011 │ 1040180 │ ██████████▍ │
50. │ LEBL │ 188956 │ 1283190 │ ████████████▋ │
51. │ YBBN │ 188011 │ 1253405 │ ████████████▌ │
52. │ LSZH │ 187934 │ 1572029 │ ███████████████▋ │
53. │ YMML │ 187643 │ 1870076 │ ██████████████████▋ │
54. │ RCTP │ 184466 │ 2773976 │ ███████████████████████████▋ │
55. │ KSNA │ 180045 │ 778484 │ ███████▋ │
56. │ EGKK │ 176420 │ 1694770 │ ████████████████▊ │
57. │ LOWW │ 176191 │ 1274833 │ ████████████▋ │
58. │ UUDD │ 176099 │ 1368226 │ █████████████▋ │
59. │ RKSI │ 173466 │ 3079026 │ ██████████████████████████████▋ │
60. │ EKCH │ 172128 │ 1229895 │ ████████████▎ │
61. │ KOAK │ 171119 │ 1114447 │ ███████████▏ │
62. │ RPLL │ 170122 │ 1440735 │ ██████████████▍ │
63. │ KRDU │ 167001 │ 830521 │ ████████▎ │
64. │ KAUS │ 164524 │ 1256198 │ ████████████▌ │
65. │ KBNA │ 163242 │ 1022726 │ ██████████▏ │
66. │ KSDF │ 162655 │ 1380867 │ █████████████▋ │
67. │ ENGM │ 160732 │ 910108 │ █████████ │
68. │ LIMC │ 160696 │ 1564620 │ ███████████████▋ │
69. │ KSJC │ 159278 │ 1081125 │ ██████████▋ │
70. │ KSTL │ 157984 │ 1026699 │ ██████████▎ │
71. │ UUWW │ 156811 │ 1261155 │ ████████████▌ │
72. │ KIND │ 153929 │ 987944 │ █████████▊ │
73. │ ESSA │ 153390 │ 1203439 │ ████████████ │
74. │ KMCO │ 153351 │ 1508657 │ ███████████████ │
75. │ KDVT │ 152895 │ 74048 │ ▋ │
76. │ VTBS │ 152645 │ 2255591 │ ██████████████████████▌ │
77. │ CYVR │ 149574 │ 2027413 │ ████████████████████▎ │
78. │ EIDW │ 148723 │ 1503985 │ ███████████████ │
79. │ LFPO │ 143277 │ 1152964 │ ███████████▌ │
80. │ EGSS │ 140830 │ 1348183 │ █████████████▍ │
81. │ KAPA │ 140776 │ 420441 │ ████▏ │
82. │ KHOU │ 138985 │ 1068806 │ ██████████▋ │
83. │ KTPA │ 138033 │ 1338223 │ █████████████▍ │
84. │ KFFZ │ 137333 │ 55397 │ ▌ │
85. │ NZAA │ 136092 │ 1581264 │ ███████████████▋ │
86. │ YPPH │ 133916 │ 1271550 │ ████████████▋ │
87. │ RJBB │ 133522 │ 1805623 │ ██████████████████ │
88. │ EDDL │ 133018 │ 1265919 │ ████████████▋ │
89. │ ULLI │ 130501 │ 1197108 │ ███████████▊ │
90. │ KIWA │ 127195 │ 250876 │ ██▌ │
91. │ KTEB │ 126969 │ 1189414 │ ███████████▊ │
92. │ VOMM │ 125616 │ 1127757 │ ███████████▎ │
93. │ LSGG │ 123998 │ 1049101 │ ██████████▍ │
94. │ LPPT │ 122733 │ 1779187 │ █████████████████▋ │
95. │ WSSS │ 120493 │ 3264122 │ ████████████████████████████████▋ │
96. │ EBBR │ 118539 │ 1579939 │ ███████████████▋ │
97. │ VTBD │ 118107 │ 661627 │ ██████▌ │
98. │ KVNY │ 116326 │ 692960 │ ██████▊ │
99. │ EDDT │ 115122 │ 941740 │ █████████▍ │
100. │ EFHK │ 114860 │ 1629143 │ ████████████████▎ │
└────────┴─────────┴──────────┴────────────────────────────────────────┘

Insert the Data?

Run the following command:

clickhouse-client --query "
INSERT INTO recipes
SELECT
title,
JSONExtract(ingredients, 'Array(String)'),
JSONExtract(directions, 'Array(String)'),
link,
source,
JSONExtract(NER, 'Array(String)')
FROM input('num UInt32, title String, ingredients String, directions String, link String, source LowCardinality(String), NER String')
FORMAT CSVWithNames
" --input_format_with_names_use_header 0 --format_csv_allow_single_quote 0 --input_format_allow_errors_num 10 < full_dataset.csv

Result:

┌─count()─┐
│ 2231141 │
└─────────┘

Result:

┌─k────────────────────┬──────c─┐
│ salt │ 890741 │
│ sugar │ 620027 │
│ butter │ 493823 │
│ flour │ 466110 │
│ eggs │ 401276 │
│ onion │ 372469 │
│ garlic │ 358364 │
│ milk │ 346769 │
│ water │ 326092 │
│ vanilla │ 270381 │
│ olive oil │ 197877 │
│ pepper │ 179305 │
│ brown sugar │ 174447 │
│ tomatoes │ 163933 │
│ egg │ 160507 │
│ baking powder │ 148277 │
│ lemon juice │ 146414 │
│ Salt │ 122557 │
│ cinnamon │ 117927 │
│ sour cream │ 116682 │
│ cream cheese │ 114423 │
│ margarine │ 112742 │
│ celery │ 112676 │
│ baking soda │ 110690 │
│ parsley │ 102151 │
│ chicken │ 101505 │
│ onions │ 98903 │
│ vegetable oil │ 91395 │
│ oil │ 85600 │
│ mayonnaise │ 84822 │
│ pecans │ 79741 │
│ nuts │ 78471 │
│ potatoes │ 75820 │
│ carrots │ 75458 │
│ pineapple │ 74345 │
│ soy sauce │ 70355 │
│ black pepper │ 69064 │
│ thyme │ 68429 │
│ mustard │ 65948 │
│ chicken broth │ 65112 │
│ bacon │ 64956 │
│ honey │ 64626 │
│ oregano │ 64077 │
│ ground beef │ 64068 │
│ unsalted butter │ 63848 │
│ mushrooms │ 61465 │
│ Worcestershire sauce │ 59328 │
│ cornstarch │ 58476 │
│ green pepper │ 58388 │
│ Cheddar cheese │ 58354 │
└──────────────────────┴────────┘

50 rows in set. Elapsed: 0.112 sec. Processed 2.23 million rows, 361.57 MB (19.99 million rows/s., 3.24 GB/s.)

Result:

┌─title────────────────────────────────────────────────────────────┬─length(NER)─┬─length(directions)─┐
│ Chocolate-Strawberry-Orange Wedding Cake │ 24 │ 126 │
│ Strawberry Cream Cheese Crumble Tart │ 19 │ 47 │
│ Charlotte-Style Ice Cream │ 11 │ 45 │
│ Sinfully Good a Million Layers Chocolate Layer Cake, With Strawb │ 31 │ 45 │
│ Sweetened Berries With Elderflower Sherbet │ 24 │ 44 │
│ Chocolate-Strawberry Mousse Cake │ 15 │ 42 │
│ Rhubarb Charlotte with Strawberries and Rum │ 20 │ 42 │
│ Chef Joey's Strawberry Vanilla Tart │ 7 │ 37 │
│ Old-Fashioned Ice Cream Sundae Cake │ 17 │ 37 │
│ Watermelon Cake │ 16 │ 36 │
└──────────────────────────────────────────────────────────────────┴─────────────┴────────────────────┘

10 rows in set. Elapsed: 0.215 sec. Processed 2.23 million rows, 1.48 GB (10.35 million rows/s., 6.86 GB/s.)

Download will take about 2 minutes with good internet connection.

Create the Table?

CREATE TABLE uk_price_paid
(
price UInt32,
date Date,
postcode1 LowCardinality(String),
postcode2 LowCardinality(String),
type Enum8('terraced' = 1, 'semi-detached' = 2, 'detached' = 3, 'flat' = 4, 'other' = 0),
is_new UInt8,
duration Enum8('freehold' = 1, 'leasehold' = 2, 'unknown' = 0),
addr1 String,
addr2 String,
street LowCardinality(String),
locality LowCardinality(String),
town LowCardinality(String),
district LowCardinality(String),
county LowCardinality(String),
category UInt8
) ENGINE = MergeTree ORDER BY (postcode1, postcode2, addr1, addr2);

It will take about 40 seconds.

Validate the Data?

Query:

SELECT count() FROM uk_price_paid;

The size of dataset in ClickHouse is just 278 MiB, check it.

Query:

SELECT formatReadableSize(total_bytes) FROM system.tables WHERE name = 'uk_price_paid';

Run Some Queries?

Query 1. Average Price Per Year?

Query:

SELECT toYear(date) AS year, round(avg(price)) AS price, bar(price, 0, 1000000, 80) FROM uk_price_paid GROUP BY year ORDER BY year;

Query 2. Average Price per Year in London?

Query:

SELECT toYear(date) AS year, round(avg(price)) AS price, bar(price, 0, 2000000, 100) FROM uk_price_paid WHERE town = 'LONDON' GROUP BY year ORDER BY year;

Something happened in 2013. I don't have a clue. Maybe you have a clue what happened in 2020?

Query 3. The Most Expensive Neighborhoods?

Query:

SELECT
town,
district,
count() AS c,
round(avg(price)) AS price,
bar(price, 0, 5000000, 100)
FROM uk_price_paid
WHERE date >= '2020-01-01'
GROUP BY
town,
district
HAVING c >= 100
ORDER BY price DESC
LIMIT 100;