ClickHouse/docs/fa/getting_started/example_datasets/nyc_taxi.md

411 lines
40 KiB
Markdown
Raw Normal View History

<div dir="rtl" markdown="1">
# داده های تاکسی New York
## چطور داده های raw را import کنیم
برای توضیحات بیشتر در ارتباط با دیتاست و موارد مربوط به دانلود به دو لینک <https://github.com/toddwschneider/nyc-taxi-data> و <http://tech.marksblogg.com/billion-nyc-taxi-rides-redshift.html> مراجعه کنید.
دانلود فایل ها حدود 277 گیگابایت داده ی غیرفشرده در قالب فایل های CSV می باشد. دانلود با استفاده ازبیش از یک کانکشن 1 Gbit نزدیک 1 ساعت طول می کشد (دانلود موازی از s3.amazonaws.com حداقل نصف کانال 1 Gbit رو جبران می کند). بعضی از فایل ها ممکن است به طول کامل دانلود نشوند. اندازه فایل ها را بررسی کنید و اگر فایلی مشکوک بود، مجددا دانلود کنید.
بعضی از فایل ها ممکن است دارای سطرهای نامعتبر باشه. با اجرای دستورات زیر این موارد برطرف می شود:
</div>
```bash
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
```
<div dir="rtl" markdown="1">
سپس داده ها باید در PostgreSQL پیش پردازش شوند. این کار نقاط انتخابی چند ضلعی را ایجاد می کند (برای مطابقت با نقاط بر روی نقشه با مناطق شهر نیویورک) و تمام داده ها را با استفاده از JOIN در یک جدول flat و denormal ترکیب می کند. برای این کار شما نیاز به نصب PostgreSQL با پشتیبانی از PostGIS دارید.
در هنگام اجرای `initialize_database.sh` مراقب باشید و به صورت دستی مجددا تمام جداول را چک کنید.
PostgreSQL تقریبا 20 تا 30 دقیقه برای پردازش هر ماه زمان نیاز میگیرد، در مجموع حدود 48 ساعت این عملیات طول می کشد.
از طریق دستور زیر شما می توانید تعداد سطرهای دانلود شده را دریافت کنید:
</div>
```text
time psql nyc-taxi-data -c "SELECT count(*) FROM trips;"
## count
1298979494
(1 row)
real 7m9.164s
```
<div dir="rtl" markdown="1">
(در یکی از پست های مقالات Mark Litwintschik این کمی بیشتر از 1.1 میلیارد سطر گزارش شده است.)
حجم داده ها در PostgreSQL 370 گیگابایت می باشد.
Export گیری داده ها از PostgreSQL:
</div>
```sql
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';
```
<div dir="rtl" markdown="1">
snapshot از داده ها با سرعت 50 مگابایت در ثانیه انجام می شود. در هنگام ایجاد snapshot، PostgreSQL داده ها را با سرعت 28 مگابایت در ثانیه از روی می خواند. این کار حدود 5 ساعت زمان میبرد. نتیجه کار فایل TSV با حجم 590612904969 بایت می باشد.
ساخت جدول temporary در ClickHouse:
</div>
```sql
CREATE TABLE trips
(
trip_id UInt32,
vendor_id String,
pickup_datetime DateTime,
dropoff_datetime Nullable(DateTime),
store_and_fwd_flag Nullable(FixedString(1)),
rate_code_id Nullable(UInt8),
pickup_longitude Nullable(Float64),
pickup_latitude Nullable(Float64),
dropoff_longitude Nullable(Float64),
dropoff_latitude Nullable(Float64),
passenger_count Nullable(UInt8),
trip_distance Nullable(Float64),
fare_amount Nullable(Float32),
extra Nullable(Float32),
mta_tax Nullable(Float32),
tip_amount Nullable(Float32),
tolls_amount Nullable(Float32),
ehail_fee Nullable(Float32),
improvement_surcharge Nullable(Float32),
total_amount Nullable(Float32),
payment_type Nullable(String),
trip_type Nullable(UInt8),
pickup Nullable(String),
dropoff Nullable(String),
cab_type Nullable(String),
precipitation Nullable(UInt8),
snow_depth Nullable(UInt8),
snowfall Nullable(UInt8),
max_temperature Nullable(UInt8),
min_temperature Nullable(UInt8),
average_wind_speed Nullable(UInt8),
pickup_nyct2010_gid Nullable(UInt8),
pickup_ctlabel Nullable(String),
pickup_borocode Nullable(UInt8),
pickup_boroname Nullable(String),
pickup_ct2010 Nullable(String),
pickup_boroct2010 Nullable(String),
pickup_cdeligibil Nullable(FixedString(1)),
pickup_ntacode Nullable(String),
pickup_ntaname Nullable(String),
pickup_puma Nullable(String),
dropoff_nyct2010_gid Nullable(UInt8),
dropoff_ctlabel Nullable(String),
dropoff_borocode Nullable(UInt8),
dropoff_boroname Nullable(String),
dropoff_ct2010 Nullable(String),
dropoff_boroct2010 Nullable(String),
dropoff_cdeligibil Nullable(String),
dropoff_ntacode Nullable(String),
dropoff_ntaname Nullable(String),
dropoff_puma Nullable(String)
) ENGINE = Log;
```
<div dir="rtl" markdown="1">
برای تبدیل فیلد ها به data type های صحیح تر و در صورت امکان، حذف NULL ها لازم است.
</div>
```text
time clickhouse-client --query="INSERT INTO trips FORMAT TabSeparated" < trips.tsv
real 75m56.214s
```
<div dir="rtl" markdown="1">
داده ها با سرعت 112 تا 140 مگابیت در ثانیه خوانده می شوند. load کردن داده ها در جدول Log Type در یک Stream، 76 دقیقه زمان کشید. این داده ها در این جدول 142 گیگابایت فضا اشغال می کنند.
(import کردن داده ها به صورت مستقیم از Postgres با استفاده از ` COPY ... TO PROGRAM` هم امکان پذیر است.)
متاسفانه، تمام فیلد های مرتبط با آب و هوا (precipitation...average_wind_speed) با Null پر شدند. به خاطر همین، ما از دیتاست نهایی اینها رو حذف کردیم.
برای شروع، ما یک جدول در یک سرور ایجاد کردیم. بعدا ما یک جدول توزیع شده می سازیم.
یک جدول خلاصه ایجاد و پر کنید:
</div>
```text
CREATE TABLE trips_mergetree
ENGINE = MergeTree(pickup_date, pickup_datetime, 8192)
AS SELECT
trip_id,
CAST(vendor_id AS Enum8('1' = 1, '2' = 2, 'CMT' = 3, 'VTS' = 4, 'DDS' = 5, 'B02512' = 10, 'B02598' = 11, 'B02617' = 12, 'B02682' = 13, 'B02764' = 14)) AS vendor_id,
toDate(pickup_datetime) AS pickup_date,
ifNull(pickup_datetime, toDateTime(0)) AS pickup_datetime,
toDate(dropoff_datetime) AS dropoff_date,
ifNull(dropoff_datetime, toDateTime(0)) AS dropoff_datetime,
assumeNotNull(store_and_fwd_flag) IN ('Y', '1', '2') AS store_and_fwd_flag,
assumeNotNull(rate_code_id) AS rate_code_id,
assumeNotNull(pickup_longitude) AS pickup_longitude,
assumeNotNull(pickup_latitude) AS pickup_latitude,
assumeNotNull(dropoff_longitude) AS dropoff_longitude,
assumeNotNull(dropoff_latitude) AS dropoff_latitude,
assumeNotNull(passenger_count) AS passenger_count,
assumeNotNull(trip_distance) AS trip_distance,
assumeNotNull(fare_amount) AS fare_amount,
assumeNotNull(extra) AS extra,
assumeNotNull(mta_tax) AS mta_tax,
assumeNotNull(tip_amount) AS tip_amount,
assumeNotNull(tolls_amount) AS tolls_amount,
assumeNotNull(ehail_fee) AS ehail_fee,
assumeNotNull(improvement_surcharge) AS improvement_surcharge,
assumeNotNull(total_amount) AS total_amount,
CAST((assumeNotNull(payment_type) AS pt) IN ('CSH', 'CASH', 'Cash', 'CAS', 'Cas', '1') ? 'CSH' : (pt IN ('CRD', 'Credit', 'Cre', 'CRE', 'CREDIT', '2') ? 'CRE' : (pt IN ('NOC', 'No Charge', 'No', '3') ? 'NOC' : (pt IN ('DIS', 'Dispute', 'Dis', '4') ? 'DIS' : 'UNK'))) AS Enum8('CSH' = 1, 'CRE' = 2, 'UNK' = 0, 'NOC' = 3, 'DIS' = 4)) AS payment_type_,
assumeNotNull(trip_type) AS trip_type,
ifNull(toFixedString(unhex(pickup), 25), toFixedString('', 25)) AS pickup,
ifNull(toFixedString(unhex(dropoff), 25), toFixedString('', 25)) AS dropoff,
CAST(assumeNotNull(cab_type) AS Enum8('yellow' = 1, 'green' = 2, 'uber' = 3)) AS cab_type,
assumeNotNull(pickup_nyct2010_gid) AS pickup_nyct2010_gid,
toFloat32(ifNull(pickup_ctlabel, '0')) AS pickup_ctlabel,
assumeNotNull(pickup_borocode) AS pickup_borocode,
CAST(assumeNotNull(pickup_boroname) AS Enum8('Manhattan' = 1, 'Queens' = 4, 'Brooklyn' = 3, '' = 0, 'Bronx' = 2, 'Staten Island' = 5)) AS pickup_boroname,
toFixedString(ifNull(pickup_ct2010, '000000'), 6) AS pickup_ct2010,
toFixedString(ifNull(pickup_boroct2010, '0000000'), 7) AS pickup_boroct2010,
CAST(assumeNotNull(ifNull(pickup_cdeligibil, ' ')) AS Enum8(' ' = 0, 'E' = 1, 'I' = 2)) AS pickup_cdeligibil,
toFixedString(ifNull(pickup_ntacode, '0000'), 4) AS pickup_ntacode,
CAST(assumeNotNull(pickup_ntaname) AS Enum16('' = 0, 'Airport' = 1, 'Allerton-Pelham Gardens' = 2, 'Annadale-Huguenot-Prince\'s Bay-Eltingville' = 3, 'Arden Heights' = 4, 'Astoria' = 5, 'Auburndale' = 6, 'Baisley Park' = 7, 'Bath Beach' = 8, 'Battery Park City-Lower Manhattan' = 9, 'Bay Ridge' = 10, 'Bayside-Bayside Hills' = 11, 'Bedford' = 12, 'Bedford Park-Fordham North' = 13, 'Bellerose' = 14, 'Belmont' = 15, 'Bensonhurst East' = 16, 'Bensonhurst West' = 17, 'Borough Park' = 18, 'Breezy Point-Belle Harbor-Rockaway Park-Broad Channel' = 19, 'Briarwood-Jamaica Hills' = 20, 'Brighton Beach' = 21, 'Bronxdale' = 22, 'Brooklyn Heights-Cobble Hill' = 23, 'Brownsville' = 24, 'Bushwick North' = 25, 'Bushwick South' = 26, 'Cambria Heights' = 27, 'Canarsie' = 28, 'Carroll Gardens-Columbia Street-Red Hook' = 29, 'Central Harlem North-Polo Grounds' = 30, 'Central Harlem South' = 31, 'Charleston-Richmond Valley-Tottenville' = 32, 'Chinatown' = 33, 'Claremont-Bathgate' = 34, 'Clinton' = 35, 'Clinton Hill' = 36, 'Co-op City' = 37, 'College Point' = 38, 'Corona' = 39, 'Crotona Park East' = 40, 'Crown Heights North' = 41, 'Crown Heights South' = 42, 'Cypress Hills-City Line' = 43, 'DUMBO-Vinegar Hill-Downtown Brooklyn-Boerum Hill' = 44, 'Douglas Manor-Douglaston-Little Neck' = 45, 'Dyker Heights' = 46, 'East Concourse-Concourse Village' = 47, 'East Elmhurst' = 48, 'East Flatbush-Farragut' = 49, 'East Flushing' = 50, 'East Harlem North' = 51, 'East Harlem South' = 52, 'East New York' = 53, 'East New York (Pennsylvania Ave)' = 54, 'East Tremont' = 55, 'East Village' = 56, 'East Williamsburg' = 57, 'Eastchester-Edenwald-Baychester' = 58, 'Elmhurst' = 59, 'Elmhurst-Maspeth' = 60, 'Erasmus' = 61, 'Far Rockaway-Bayswater' = 62, 'Flatbush' = 63, 'Flatlands' = 64, 'Flushing' = 65, 'Fordham South' = 66, 'Forest Hills' = 67, 'Fort Greene' = 68, 'Fresh Meadows-Utopia' = 69, 'Ft. Totten-Bay Terrace-Clearview' = 70, 'Georgetown-Marine Park-Bergen Beach-Mill Basin' = 71, 'Glen Oaks-Floral Park-New Hyde Park' = 72, 'Glendale' = 73, 'Gramercy' = 74, 'Grasmere-Arrochar-Ft. Wadsworth' = 75, 'Gravesend' = 76, 'Great Kills' = 77, 'Greenpoint' = 78, 'Grymes Hill-Clifton-Fox Hills' = 79, 'Hamilton Heights' = 80, 'Hammels-Arverne-Edgemere' = 81, 'Highbridge' = 82, 'Hollis' = 83, 'Homecrest' = 84, 'Hudson Yards-Chelsea-Flatiron-Union Square' = 85, 'Hunters Point-Sunnyside-West Maspeth' = 86, 'Hunts Point' = 87, 'Jackson Heights' = 88, 'Jamaica' = 89, 'Jamaica Estates-Holliswood' = 90, 'Kensington-Ocean Parkway' = 91, 'Kew Gardens' = 92, 'Kew Gardens Hills' = 93, 'Kingsbridge Heights' = 94, 'Laurelton' = 95, 'Lenox Hill-Roosevelt Island' = 96, 'Lincoln Square' = 97, 'Lindenwood-Howard Beach' = 98, 'Longwood' = 99, 'Lower East Side' = 100, 'Madison' = 101, 'Manhattanville' = 102, 'Marble Hill-Inwood' = 103, 'Mariner\'s Harbor-Arlington-Port Ivory-Graniteville' = 104, 'Maspeth' = 105, 'Melrose South-Mott Haven North' = 106, 'Middle Village' = 107, 'Midtown-Midtown South' = 108, 'Midwood' = 109, 'Morningside Heights' = 110, 'Morrisania-Melrose' = 111, 'Mott Haven-Port Morris' = 112, 'Mount Hope' = 113, 'Murray Hill' = 114, 'Murray Hill-Kips Bay' = 115, 'New Brighton-Silver Lake' = 116, 'New Dorp-Midland Beach' = 117, 'New Springville-Bloomfield-Travis' = 118, 'North Corona' = 119, 'North Riverdale-Fieldston-Riverdale' = 120, 'North Side-South Side' = 121, 'Norwood' = 122, 'Oakland Gardens' = 123, 'Oakwood-Oakwood Beach' = 124, 'Ocean Hill' = 125, 'Ocean Parkway South' = 126, 'Old Astoria' = 127, 'Old Town-Dongan Hills-South Beach' = 128, 'Ozone Park' = 129, 'Park Slope-Gowanus' = 130, 'Parkchester' = 131, 'Pelham Bay-Country Club-City Island' = 132, 'Pelham Parkway' = 133, 'Pomonok-Flushing Heights-Hillcrest' = 134, 'Port Richmond' = 135, 'Prospect Heights' = 136, 'Prospect Lefferts Gardens-Wingate' = 137, 'Queens Village' = 138, 'Queensboro Hill' = 139, 'Queensbridge-Ravenswood-Long Island City' = 140, 'Rego Park' = 141, 'Richmond Hill' = 142, 'Ridgewood' = 143, 'Rikers Island' = 144, 'Rosedale' = 145, 'Rossville-Woodrow' = 146, 'Rugby-Remsen Village' = 147, 'S
toUInt16(ifNull(pickup_puma, '0')) AS pickup_puma,
assumeNotNull(dropoff_nyct2010_gid) AS dropoff_nyct2010_gid,
toFloat32(ifNull(dropoff_ctlabel, '0')) AS dropoff_ctlabel,
assumeNotNull(dropoff_borocode) AS dropoff_borocode,
CAST(assumeNotNull(dropoff_boroname) AS Enum8('Manhattan' = 1, 'Queens' = 4, 'Brooklyn' = 3, '' = 0, 'Bronx' = 2, 'Staten Island' = 5)) AS dropoff_boroname,
toFixedString(ifNull(dropoff_ct2010, '000000'), 6) AS dropoff_ct2010,
toFixedString(ifNull(dropoff_boroct2010, '0000000'), 7) AS dropoff_boroct2010,
CAST(assumeNotNull(ifNull(dropoff_cdeligibil, ' ')) AS Enum8(' ' = 0, 'E' = 1, 'I' = 2)) AS dropoff_cdeligibil,
toFixedString(ifNull(dropoff_ntacode, '0000'), 4) AS dropoff_ntacode,
CAST(assumeNotNull(dropoff_ntaname) AS Enum16('' = 0, 'Airport' = 1, 'Allerton-Pelham Gardens' = 2, 'Annadale-Huguenot-Prince\'s Bay-Eltingville' = 3, 'Arden Heights' = 4, 'Astoria' = 5, 'Auburndale' = 6, 'Baisley Park' = 7, 'Bath Beach' = 8, 'Battery Park City-Lower Manhattan' = 9, 'Bay Ridge' = 10, 'Bayside-Bayside Hills' = 11, 'Bedford' = 12, 'Bedford Park-Fordham North' = 13, 'Bellerose' = 14, 'Belmont' = 15, 'Bensonhurst East' = 16, 'Bensonhurst West' = 17, 'Borough Park' = 18, 'Breezy Point-Belle Harbor-Rockaway Park-Broad Channel' = 19, 'Briarwood-Jamaica Hills' = 20, 'Brighton Beach' = 21, 'Bronxdale' = 22, 'Brooklyn Heights-Cobble Hill' = 23, 'Brownsville' = 24, 'Bushwick North' = 25, 'Bushwick South' = 26, 'Cambria Heights' = 27, 'Canarsie' = 28, 'Carroll Gardens-Columbia Street-Red Hook' = 29, 'Central Harlem North-Polo Grounds' = 30, 'Central Harlem South' = 31, 'Charleston-Richmond Valley-Tottenville' = 32, 'Chinatown' = 33, 'Claremont-Bathgate' = 34, 'Clinton' = 35, 'Clinton Hill' = 36, 'Co-op City' = 37, 'College Point' = 38, 'Corona' = 39, 'Crotona Park East' = 40, 'Crown Heights North' = 41, 'Crown Heights South' = 42, 'Cypress Hills-City Line' = 43, 'DUMBO-Vinegar Hill-Downtown Brooklyn-Boerum Hill' = 44, 'Douglas Manor-Douglaston-Little Neck' = 45, 'Dyker Heights' = 46, 'East Concourse-Concourse Village' = 47, 'East Elmhurst' = 48, 'East Flatbush-Farragut' = 49, 'East Flushing' = 50, 'East Harlem North' = 51, 'East Harlem South' = 52, 'East New York' = 53, 'East New York (Pennsylvania Ave)' = 54, 'East Tremont' = 55, 'East Village' = 56, 'East Williamsburg' = 57, 'Eastchester-Edenwald-Baychester' = 58, 'Elmhurst' = 59, 'Elmhurst-Maspeth' = 60, 'Erasmus' = 61, 'Far Rockaway-Bayswater' = 62, 'Flatbush' = 63, 'Flatlands' = 64, 'Flushing' = 65, 'Fordham South' = 66, 'Forest Hills' = 67, 'Fort Greene' = 68, 'Fresh Meadows-Utopia' = 69, 'Ft. Totten-Bay Terrace-Clearview' = 70, 'Georgetown-Marine Park-Bergen Beach-Mill Basin' = 71, 'Glen Oaks-Floral Park-New Hyde Park' = 72, 'Glendale' = 73, 'Gramercy' = 74, 'Grasmere-Arrochar-Ft. Wadsworth' = 75, 'Gravesend' = 76, 'Great Kills' = 77, 'Greenpoint' = 78, 'Grymes Hill-Clifton-Fox Hills' = 79, 'Hamilton Heights' = 80, 'Hammels-Arverne-Edgemere' = 81, 'Highbridge' = 82, 'Hollis' = 83, 'Homecrest' = 84, 'Hudson Yards-Chelsea-Flatiron-Union Square' = 85, 'Hunters Point-Sunnyside-West Maspeth' = 86, 'Hunts Point' = 87, 'Jackson Heights' = 88, 'Jamaica' = 89, 'Jamaica Estates-Holliswood' = 90, 'Kensington-Ocean Parkway' = 91, 'Kew Gardens' = 92, 'Kew Gardens Hills' = 93, 'Kingsbridge Heights' = 94, 'Laurelton' = 95, 'Lenox Hill-Roosevelt Island' = 96, 'Lincoln Square' = 97, 'Lindenwood-Howard Beach' = 98, 'Longwood' = 99, 'Lower East Side' = 100, 'Madison' = 101, 'Manhattanville' = 102, 'Marble Hill-Inwood' = 103, 'Mariner\'s Harbor-Arlington-Port Ivory-Graniteville' = 104, 'Maspeth' = 105, 'Melrose South-Mott Haven North' = 106, 'Middle Village' = 107, 'Midtown-Midtown South' = 108, 'Midwood' = 109, 'Morningside Heights' = 110, 'Morrisania-Melrose' = 111, 'Mott Haven-Port Morris' = 112, 'Mount Hope' = 113, 'Murray Hill' = 114, 'Murray Hill-Kips Bay' = 115, 'New Brighton-Silver Lake' = 116, 'New Dorp-Midland Beach' = 117, 'New Springville-Bloomfield-Travis' = 118, 'North Corona' = 119, 'North Riverdale-Fieldston-Riverdale' = 120, 'North Side-South Side' = 121, 'Norwood' = 122, 'Oakland Gardens' = 123, 'Oakwood-Oakwood Beach' = 124, 'Ocean Hill' = 125, 'Ocean Parkway South' = 126, 'Old Astoria' = 127, 'Old Town-Dongan Hills-South Beach' = 128, 'Ozone Park' = 129, 'Park Slope-Gowanus' = 130, 'Parkchester' = 131, 'Pelham Bay-Country Club-City Island' = 132, 'Pelham Parkway' = 133, 'Pomonok-Flushing Heights-Hillcrest' = 134, 'Port Richmond' = 135, 'Prospect Heights' = 136, 'Prospect Lefferts Gardens-Wingate' = 137, 'Queens Village' = 138, 'Queensboro Hill' = 139, 'Queensbridge-Ravenswood-Long Island City' = 140, 'Rego Park' = 141, 'Richmond Hill' = 142, 'Ridgewood' = 143, 'Rikers Island' = 144, 'Rosedale' = 145, 'Rossville-Woodrow' = 146, 'Rugby-Remsen Village' = 147, '
toUInt16(ifNull(dropoff_puma, '0')) AS dropoff_puma
FROM trips
```
<div dir="rtl" markdown="1">
این کار با سرعت 428 هزار رکورد در ثانیه و 3030 ثانیه طول خواهد کشید. برای load سریعتر، شما می توانید یک جدول با موتور `Log` به جای `MergeTree` بسازید. در این مورد، دانلود سریعتر از 200 ثانیه کار می کند.
این جدول 126 گیابایت فضا بر روی دیسک اشغال می کند.
</div>
```text
:) SELECT formatReadableSize(sum(bytes)) FROM system.parts WHERE table = 'trips_mergetree' AND active
SELECT formatReadableSize(sum(bytes))
FROM system.parts
WHERE (table = 'trips_mergetree') AND active
┌─formatReadableSize(sum(bytes))─┐
│ 126.18 GiB │
└────────────────────────────────┘
```
<div dir="rtl" markdown="1">
در میان چیزهای دیگر، شما می تونید از دستور OPTIMIZE بر روی MergeTree استفاده کنید. اما از آنجایی که بدون این دستور همه چیز خوب است، اجرای این دستور ضروری نیست..
## نتایج بر روی یک سرور
</div>
Q1:
```sql
SELECT cab_type, count(*) FROM trips_mergetree GROUP BY cab_type
```
0.490 seconds.
Q2:
```sql
SELECT passenger_count, avg(total_amount) FROM trips_mergetree GROUP BY passenger_count
```
1.224 seconds.
Q3:
```sql
SELECT passenger_count, toYear(pickup_date) AS year, count(*) FROM trips_mergetree GROUP BY passenger_count, year
```
2.104 seconds.
Q4:
```sql
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
```
3.593 seconds.
<div dir="rtl" markdown="1">
کانفیگ سرور به این صورت بود:
Two Intel(R) Xeon(R) CPU E5-2650 v2 @ 2.60GHz, 16 physical kernels total,
128 GiB RAM,
8x6 TB HD on hardware RAID-5
زمان اجرا query ها از زمان دومین اجرا بهتر می شود، چون query ها داده ها رو از فایل system cache می خوانند. در ادامه cache دیگری رخ نمیدهد: داده ها در هر اجرا خوانده و پردازش شده اند.
ساخت جداول در در سه سرور:
در هر سرور دستور زیر را اجرا کنید:
</div>
```text
CREATE TABLE default.trips_mergetree_third ( trip_id UInt32, vendor_id Enum8('1' = 1, '2' = 2, 'CMT' = 3, 'VTS' = 4, 'DDS' = 5, 'B02512' = 10, 'B02598' = 11, 'B02617' = 12, 'B02682' = 13, 'B02764' = 14), pickup_date Date, pickup_datetime DateTime, dropoff_date Date, dropoff_datetime DateTime, store_and_fwd_flag UInt8, rate_code_id UInt8, pickup_longitude Float64, pickup_latitude Float64, dropoff_longitude Float64, dropoff_latitude Float64, passenger_count UInt8, trip_distance Float64, fare_amount Float32, extra Float32, mta_tax Float32, tip_amount Float32, tolls_amount Float32, ehail_fee Float32, improvement_surcharge Float32, total_amount Float32, payment_type_ Enum8('UNK' = 0, 'CSH' = 1, 'CRE' = 2, 'NOC' = 3, 'DIS' = 4), trip_type UInt8, pickup FixedString(25), dropoff FixedString(25), cab_type Enum8('yellow' = 1, 'green' = 2, 'uber' = 3), pickup_nyct2010_gid UInt8, pickup_ctlabel Float32, pickup_borocode UInt8, pickup_boroname Enum8('' = 0, 'Manhattan' = 1, 'Bronx' = 2, 'Brooklyn' = 3, 'Queens' = 4, 'Staten Island' = 5), pickup_ct2010 FixedString(6), pickup_boroct2010 FixedString(7), pickup_cdeligibil Enum8(' ' = 0, 'E' = 1, 'I' = 2), pickup_ntacode FixedString(4), pickup_ntaname Enum16('' = 0, 'Airport' = 1, 'Allerton-Pelham Gardens' = 2, 'Annadale-Huguenot-Prince\'s Bay-Eltingville' = 3, 'Arden Heights' = 4, 'Astoria' = 5, 'Auburndale' = 6, 'Baisley Park' = 7, 'Bath Beach' = 8, 'Battery Park City-Lower Manhattan' = 9, 'Bay Ridge' = 10, 'Bayside-Bayside Hills' = 11, 'Bedford' = 12, 'Bedford Park-Fordham North' = 13, 'Bellerose' = 14, 'Belmont' = 15, 'Bensonhurst East' = 16, 'Bensonhurst West' = 17, 'Borough Park' = 18, 'Breezy Point-Belle Harbor-Rockaway Park-Broad Channel' = 19, 'Briarwood-Jamaica Hills' = 20, 'Brighton Beach' = 21, 'Bronxdale' = 22, 'Brooklyn Heights-Cobble Hill' = 23, 'Brownsville' = 24, 'Bushwick North' = 25, 'Bushwick South' = 26, 'Cambria Heights' = 27, 'Canarsie' = 28, 'Carroll Gardens-Columbia Street-Red Hook' = 29, 'Central Harlem North-Polo Grounds' = 30, 'Central Harlem South' = 31, 'Charleston-Richmond Valley-Tottenville' = 32, 'Chinatown' = 33, 'Claremont-Bathgate' = 34, 'Clinton' = 35, 'Clinton Hill' = 36, 'Co-op City' = 37, 'College Point' = 38, 'Corona' = 39, 'Crotona Park East' = 40, 'Crown Heights North' = 41, 'Crown Heights South' = 42, 'Cypress Hills-City Line' = 43, 'DUMBO-Vinegar Hill-Downtown Brooklyn-Boerum Hill' = 44, 'Douglas Manor-Douglaston-Little Neck' = 45, 'Dyker Heights' = 46, 'East Concourse-Concourse Village' = 47, 'East Elmhurst' = 48, 'East Flatbush-Farragut' = 49, 'East Flushing' = 50, 'East Harlem North' = 51, 'East Harlem South' = 52, 'East New York' = 53, 'East New York (Pennsylvania Ave)' = 54, 'East Tremont' = 55, 'East Village' = 56, 'East Williamsburg' = 57, 'Eastchester-Edenwald-Baychester' = 58, 'Elmhurst' = 59, 'Elmhurst-Maspeth' = 60, 'Erasmus' = 61, 'Far Rockaway-Bayswater' = 62, 'Flatbush' = 63, 'Flatlands' = 64, 'Flushing' = 65, 'Fordham South' = 66, 'Forest Hills' = 67, 'Fort Greene' = 68, 'Fresh Meadows-Utopia' = 69, 'Ft. Totten-Bay Terrace-Clearview' = 70, 'Georgetown-Marine Park-Bergen Beach-Mill Basin' = 71, 'Glen Oaks-Floral Park-New Hyde Park' = 72, 'Glendale' = 73, 'Gramercy' = 74, 'Grasmere-Arrochar-Ft. Wadsworth' = 75, 'Gravesend' = 76, 'Great Kills' = 77, 'Greenpoint' = 78, 'Grymes Hill-Clifton-Fox Hills' = 79, 'Hamilton Heights' = 80, 'Hammels-Arverne-Edgemere' = 81, 'Highbridge' = 82, 'Hollis' = 83, 'Homecrest' = 84, 'Hudson Yards-Chelsea-Flatiron-Union Square' = 85, 'Hunters Point-Sunnyside-West Maspeth' = 86, 'Hunts Point' = 87, 'Jackson Heights' = 88, 'Jamaica' = 89, 'Jamaica Estates-Holliswood' = 90, 'Kensington-Ocean Parkway' = 91, 'Kew Gardens' = 92, 'Kew Gardens Hills' = 93, 'Kingsbridge Heights' = 94, 'Laurelton' = 95, 'Lenox Hill-Roosevelt Island' = 96, 'Lincoln Square' = 97, 'Lindenwood-Howard Beach' = 98, 'Longwood' = 99, 'Lower East Side' = 100, 'Madison' = 101, 'Manhattanville' = 102, 'Marble Hill-Inwood' = 103, 'Mariner\'s Harbor-Arlington-Port Ivory-Graniteville' = 104, 'Maspeth' = 105,
```
<div dir="rtl" markdown="1">
بر روی سرور source دستور زیر را وارد کنید:
</div>
```sql
CREATE TABLE trips_mergetree_x3 AS trips_mergetree_third ENGINE = Distributed(perftest, default, trips_mergetree_third, rand())
```
<div dir="rtl" markdown="1">
query زیر دادها را توزیع مجدد می کند:
</div>
```sql
INSERT INTO trips_mergetree_x3 SELECT * FROM trips_mergetree
```
<div dir="rtl" markdown="1">
این query 2454 ثانیه زمان میبرد.
در سه سرور:
Q1: 0.212 ثانیه.
Q2: 0.438 ثانیه.
Q3: 0.733 ثانیه.
Q4: 1.241 ثانیه.
از آنجایی که query ها به صورت خطی scale شده اند، از نتایج به دست آمده شگفتی وجود ندارد.
ما همچنین نتایج زیر را از اجرای این query در کلاستر 140 سرور دریافت کردیم:
Q1: 0.028 ثانیه.
Q2: 0.043 ثانیه.
Q3: 0.051 ثانیه.
Q4: 0.072 ثانیه.
در این مورد، زمان پردازش query براساس latency شبکه مشخص می شود. ما این query ها را با استفاده از یک مشتری واقع در دیتاسنتر Yandex در فنلاند در یک کلاستر روسیه دریافت کردیم، که latency آن حدود 20 میلی ثانیه به نتایج اضافه کرد.
## نتایج
| نودها | Q1 | Q2 | Q3 | Q4 |
| ----- | ----- | ----- | ----- | ----- |
| 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 |
</div>