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  • SequenceFile,RCFile格式的表不能直接从本地文件导入数据

    hive有textFile,SequenceFile,RCFile三种文件格式。

    其中textfile为默认格式,建表时不指定默认为这个格式,导入数据时会直接把数据文件拷贝到hdfs上不进行处理。

    SequenceFile,RCFile格式的表不能直接从本地文件导入数据,数据要先导入到textfile格式的表中,然后再从textfile表中用insert导入到SequenceFile,RCFile表中。

    写道
    create table zone0000tf(ra int, dec int, mag int) row format delimited fields terminated by '|';
    create table zone0000rc(ra int, dec int, mag int) row format delimited fields terminated by '|' stored as rcfile;

    load data local inpath '/home/cq/usnoa/zone0000.asc ' into table zone0000tf;
    insert overwrite table zone0000rc select * from zone0000tf;(begin a job)
     

    File Format

     

    TextFile

    SequenceFIle

    RCFFile

    Data type

    Text Only

    Text/Binary

    Text/Binary

    Internal Storage Order

    Row-based

    Row-based

    Column-based

    Compression

    File Based

    Block Based

    Block Based

    Splitable

    YES

    YES

    YES

    Splitable After Compression

    No

    YES

    YES

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  • 原文地址:https://www.cnblogs.com/tangtianfly/p/2549683.html
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