ORC SerDe

Utilizzate il ORC SerDe per creare tabelle Athena a partire dai ORC dati.

Nome della libreria di serializzazione

La libreria di serializzazione per ORC SerDe èorg.apache.hadoop.hive.ql.io.orc.OrcSerde, ma nelle tue CREATE TABLE istruzioni lo specifichi con la clausola. STORED AS ORC Per informazioni sul codice sorgente, OrcSerdevedi.java su .com. GitHub

Esempio: creare una tabella per i dati di ORC volo

Nota

Replace (Sostituisci) myregion accedi s3://athena-examples-myregion/path/to/data/ con l'identificatore della regione in cui esegui Athena, ad esempio. s3://athena-examples-us-west-1/path/to/data/

L'esempio seguente crea una tabella per i dati sui ritardi dei voli. ORC La tabella include partizioni:

DROP TABLE flight_delays_orc;
CREATE EXTERNAL TABLE flight_delays_orc (
    yr INT,
    quarter INT,
    month INT,
    dayofmonth INT,
    dayofweek INT,
    flightdate STRING,
    uniquecarrier STRING,
    airlineid INT,
    carrier STRING,
    tailnum STRING,
    flightnum STRING,
    originairportid INT,
    originairportseqid INT,
    origincitymarketid INT,
    origin STRING,
    origincityname STRING,
    originstate STRING,
    originstatefips STRING,
    originstatename STRING,
    originwac INT,
    destairportid INT,
    destairportseqid INT,
    destcitymarketid INT,
    dest STRING,
    destcityname STRING,
    deststate STRING,
    deststatefips STRING,
    deststatename STRING,
    destwac INT,
    crsdeptime STRING,
    deptime STRING,
    depdelay INT,
    depdelayminutes INT,
    depdel15 INT,
    departuredelaygroups INT,
    deptimeblk STRING,
    taxiout INT,
    wheelsoff STRING,
    wheelson STRING,
    taxiin INT,
    crsarrtime INT,
    arrtime STRING,
    arrdelay INT,
    arrdelayminutes INT,
    arrdel15 INT,
    arrivaldelaygroups INT,
    arrtimeblk STRING,
    cancelled INT,
    cancellationcode STRING,
    diverted INT,
    crselapsedtime INT,
    actualelapsedtime INT,
    airtime INT,
    flights INT,
    distance INT,
    distancegroup INT,
    carrierdelay INT,
    weatherdelay INT,
    nasdelay INT,
    securitydelay INT,
    lateaircraftdelay INT,
    firstdeptime STRING,
    totaladdgtime INT,
    longestaddgtime INT,
    divairportlandings INT,
    divreacheddest INT,
    divactualelapsedtime INT,
    divarrdelay INT,
    divdistance INT,
    div1airport STRING,
    div1airportid INT,
    div1airportseqid INT,
    div1wheelson STRING,
    div1totalgtime INT,
    div1longestgtime INT,
    div1wheelsoff STRING,
    div1tailnum STRING,
    div2airport STRING,
    div2airportid INT,
    div2airportseqid INT,
    div2wheelson STRING,
    div2totalgtime INT,
    div2longestgtime INT,
    div2wheelsoff STRING,
    div2tailnum STRING,
    div3airport STRING,
    div3airportid INT,
    div3airportseqid INT,
    div3wheelson STRING,
    div3totalgtime INT,
    div3longestgtime INT,
    div3wheelsoff STRING,
    div3tailnum STRING,
    div4airport STRING,
    div4airportid INT,
    div4airportseqid INT,
    div4wheelson STRING,
    div4totalgtime INT,
    div4longestgtime INT,
    div4wheelsoff STRING,
    div4tailnum STRING,
    div5airport STRING,
    div5airportid INT,
    div5airportseqid INT,
    div5wheelson STRING,
    div5totalgtime INT,
    div5longestgtime INT,
    div5wheelsoff STRING,
    div5tailnum STRING
)
PARTITIONED BY (year String)
STORED AS ORC
LOCATION 's3://athena-examples-myregion/flight/orc/'
tblproperties ("orc.compress"="ZLIB");

Esegui l'istruzione MSCK REPAIR TABLE sulla tabella per aggiornare i metadati della partizione:

MSCK REPAIR TABLE flight_delays_orc;

Utilizza questa query per ottenere i primi 10 voli in ritardo da più di 1 ora:

SELECT origin, dest, count(*) as delays
FROM flight_delays_orc
WHERE depdelayminutes > 60
GROUP BY origin, dest
ORDER BY 3 DESC
LIMIT 10;