Hive支持的文件格式与压缩算法

概述


只要是配置了正确的文件类型和压缩类型(比如Textfile+Gzip、SequenceFile+Snappy等),Hive都可以预期读取并解析数据,提供SQL功能。
SequenceFile本身的结构已经设计了内容进行压缩。所以对于SequenceFile文件的压缩,并不是先生成SequenceFile文件,再对文件进行压缩。而是生成SequenceFile文件时,对其中的内容字段进行压缩。最终压缩后,对外仍体现为一个SequenceFile。
RCFile、ORCFile、Parquet、Avro对于压缩的处理方式与SequenceFile相同。

文件格式
  Textfile
  SequenceFile
  RCFile
  ORCFile
  Parquet
  Avro

压缩算法的编解码器

序号 压缩格式 算法 多文件 可分割性 工具 工具压缩后扩展名
1 DEFLATE DEFLATE .deflate
2 Gzip DEFLATE gzip .gz
3 bzip2 bzip2 bzip2 .bz2
4 LZO LZO lzop .lzo
5 LZ4 ?? ?? ?? ?? ??
6 Snappy ?? ?? ?? ?? ??
7 ZLIB ?? ?? ?? ?? ??
8 ZIP DEFLATE 是,在文件范围内 zip .zip

一、TEXTFILE

1、文本文件,非压缩

文本文件格式
文件文件(TEXTFILE)格式是Hive中默认的存储格式,在创建Hive 表时如果不指定存储格式即为文本文件。文本文件中每一行数据就是一条记录,可以用任意的分隔符进行分割,也方便和其他的工具进行数据共享、查看和编辑,比如sed,awk等。但相对于二进制文件,文本文件存储的空间较大。
TEXTFILE的数据不做压缩,磁盘开销大,数据解析开销大。可结合Gzip、Bzip2、Snappy等使用(系统自动检查,执行查询时自动解压),但使用这种方式,hive不会对数据进行切分,从而无法对数据进行并行操作

--创建一个表,格式为文本文件:

CREATE EXTERNAL TABLE student_text (id STRING, name STRING)

ROW FORMAT DELIMITED 
 
    FIELDS TERMINATED BY ',' 
 
    LINES TERMINATED BY '
'

STORED AS TEXTFILE;

--导入数据到此表中,将启动MR任务

INSERT OVERWRITE TABLE student_text SELECT * FROM student;

可查看到生成的数据文件的格式为非压缩的文本文件:

hdfs dfs -cat /user/hive/warehouse/student_text/000000_0

1001810081,cheyo
1001810082,pku
1001810083,rocky
1001810084,stephen
2002820081,sql
2002820082,hello
2002820083,hijj
3001810081,hhhhhhh
3001810082,abbbbbb

2、文本文件,DEFLATE压缩

--创建一个表,格式为文件文件:

CREATE TABLE student_text_def (id STRING, name STRING)

ROW FORMAT DELIMITED
 
    FIELDS TERMINATED BY ','
 
    LINES TERMINATED BY '
'

STORED AS TEXTFILE;

--设置压缩类型为DEFLATE压缩

SET hive.exec.compress.output=true;

SET mapred.output.compress=true;

SET mapred.output.compression.codec=org.apache.hadoop.io.compress.DefaultCodec; 

--导入数据:

INSERT OVERWRITE TABLE student_text_def SELECT * FROM student;

--查看数据

SELECT * FROM student_text_def;

查看数据文件,可看到数据文件为多个.deflate文件。

hdfs dfs -ls /user/hive/warehouse/student_text_def/
-rw-r--r--   2015-09-16 12:48 /user/hive/warehouse/student_text_def/000000_0.deflate
-rw-r--r--   2015-09-16 12:48 /user/hive/warehouse/student_text_def/000001_0.deflate
-rw-r--r--   2015-09-16 12:48 /user/hive/warehouse/student_text_def/000002_0.deflate

3、文本文件,Gzip压缩

--创建一个表,格式为文件文件:

CREATE TABLE student_text_gzip (id STRING, name STRING)

ROW FORMAT DELIMITED
 
    FIELDS TERMINATED BY ','
 
    LINES TERMINATED BY '
'

STORED AS TEXTFILE;

--设置压缩类型为Gzip压缩

SET hive.exec.compress.output=true;

SET mapred.output.compress=true;

SET mapred.output.compression.codec=org.apache.hadoop.io.compress.GzipCodec;

--导入数据:

INSERT OVERWRITE TABLE student_text_gzip SELECT * FROM student;

--查看数据
S
SELECT * FROM student_text_gzip;

查看数据文件,可看到数据文件为多个.gz文件。解开.gz文件,可以看到明文文本:

hdfs dfs -ls /user/hive/warehouse/student_text_gzip/
-rw-r--r--  2015-09-15 10:03 /user/hive/warehouse/student_text_gzip/000000_0.gz
-rw-r--r--  2015-09-15 10:03 /user/hive/warehouse/student_text_gzip/000001_0.gz
-rw-r--r--  2015-09-15 10:03 /user/hive/warehouse/student_text_gzip/000002_0.gz

4、文本文件,Bzip2压缩

--创建一个表,格式为文件文件:

CREATE TABLE student_text_bzip2 (id STRING, name STRING)

ROW FORMAT DELIMITED
 
    FIELDS TERMINATED BY ','
 
    LINES TERMINATED BY '
'

STORED AS TEXTFILE;
-
--设置压缩类型为Bzip2压缩:

SET hive.exec.compress.output=true;

SET mapred.output.compress=true;

SET mapred.output.compression.codec=org.apache.hadoop.io.compress.BZip2Codec;

--导入数据

INSERT OVERWRITE TABLE student_text_bzip2 SELECT * FROM student;

--查看数据:

SELECT * FROM student_text_bzip2;

查看数据文件,可看到数据文件为多个.bz2文件。解开.bz2文件,可以看到明文文本:

hdfs dfs -ls /user/hive/warehouse/student_text_bzip2
-rw-r--r--  2015-09-15 10:09 /user/hive/warehouse/student_text_bzip2/000000_0.bz2
-rw-r--r--  2015-09-15 10:09 /user/hive/warehouse/student_text_bzip2/000001_0.bz2
-rw-r--r--  2015-09-15 10:09 /user/hive/warehouse/student_text_bzip2/000002_0.bz2

5、文本文件,lzo压缩

--创建表
C
CREATE TABLE student_text_lzo (id STRING, name STRING)

ROW FORMAT DELIMITED
 
    FIELDS TERMINATED BY ','
 
    LINES TERMINATED BY '
'

STORED AS TEXTFILE;

--设置为LZO压缩

SET hive.exec.compress.output=true;

SET mapred.output.compress=true;

SET mapred.output.compression.codec=com.hadoop.compression.lzo.LzopCodec;

--导入数据

INSERT OVERWRITE TABLE student_text_lzo SELECT * FROM student;

--查询数据

SELECT * FROM student_text_lzo;
create external table `cp_api_log`(`line` string)
partitioned by (`date` string)
stored as INPUTFORMAT 'com.hadoop.mapred.DeprecatedLzoTextInputFormat' 
OUTPUTFORMAT 'org.apache.hadoop.hive.ql.io.HiveIgnoreKeyTextOutputFormat' 
location 'hdfs://hdfs://BigdataCluster/user/hive/warehouse/sm_data.db/ods/ods_cp_api'

查看数据文件,可看到数据文件为多个.lzo压缩。解开.lzo文件,可以看到明文文本。
未实测,需要安装lzop库

6、文本文件,lz4压缩

--创建表
C
CREATE TABLE student_text_lz4 (id STRING, name STRING)

ROW FORMAT DELIMITED
 
    FIELDS TERMINATED BY ','
 
    LINES TERMINATED BY '
'

STORED AS TEXTFILE;

--设置为LZ4压缩

SET hive.exec.compress.output=true;

SET mapred.output.compress=true;

SET mapred.output.compression.codec=org.apache.hadoop.io.compress.Lz4Codec;

--导入数据

INSERT OVERWRITE TABLE student_text_lz4 SELECT * FROM student;

查看数据文件,可看到数据文件为多个.lz4压缩。使用ls查看.lz4文件,可以看到是压缩后的文本。

hdfs dfs -ls /user/hive/warehouse/student_text_lz4
-rw-r--r-- 2015-09-16 12:06 /user/hive/warehouse/student_text_lz4/000000_0.lz4
-rw-r--r-- 2015-09-16 12:06 /user/hive/warehouse/student_text_lz4/000001_0.lz4
-rw-r--r-- 2015-09-16 12:06 /user/hive/warehouse/student_text_lz4/000002_0.lz4

7、文本文件,Snappy压缩

--创建表
C
CREATE TABLE student_text_snappy (id STRING, name STRING)

ROW FORMAT DELIMITED
 
    FIELDS TERMINATED BY ','
 
    LINES TERMINATED BY '
'

STORED AS TEXTFILE;

--设置压缩

SET hive.exec.compress.output=true;

SET mapred.compress.map.output=true;

SET mapred.output.compress=true;

SET mapred.output.compression=org.apache.hadoop.io.compress.SnappyCodec;

SET mapred.output.compression.codec=org.apache.hadoop.io.compress.SnappyCodec;

SET io.compression.codecs=org.apache.hadoop.io.compress.SnappyCodec;

--导入数据

INSERT OVERWRITE TABLE student_text_snappy SELECT * FROM student;

--查询数据

SELECT * FROM student_text_snappy;

查看数据文件,可看到数据文件为多个.snappy压缩文件。使用ls查看.snappy文件,可以看到是压缩后的文本:

hdfs dfs -ls /user/hive/warehouse/student_text_snappy
Found 3 items
-rw-r--r--   2015-09-15 16:42 /user/hive/warehouse/student_text_snappy/000000_0.snappy
-rw-r--r--   2015-09-15 16:42 /user/hive/warehouse/student_text_snappy/000001_0.snappy
-rw-r--r--   2015-09-15 16:42 /user/hive/warehouse/student_text_snappy/000002_0.snappy

二、SEQUENCEFILE

1、Sequence文件,DEFLATE压缩

--创建一个表,格式为文件文件:

CREATE TABLE student_seq_def (id STRING, name STRING)

ROW FORMAT DELIMITED
 
    FIELDS TERMINATED BY ','
 
    LINES TERMINATED BY '
'

STORED AS SEQUENCEFILE;

--设置压缩类型为Gzip压缩

SET hive.exec.compress.output=true;

SET mapred.output.compress=true;

SET mapred.output.compression.codec=org.apache.hadoop.io.compress.DefaultCodec; 

--导入数据:

INSERT OVERWRITE TABLE student_seq_def SELECT * FROM student;

--查看数据

SELECT * FROM student_seq_def;

查看数据文件,是一个密文的文件.

hdfs dfs -ls /user/hive/warehouse/student_seq_def/
-rw-r--r--  /user/hive/warehouse/student_seq_def/000000_0

2、Sequence文件,Gzip压缩

--创建一个表,格式为文件文件:

CREATE TABLE student_seq_gzip (id STRING, name STRING)

ROW FORMAT DELIMITED
 
    FIELDS TERMINATED BY ','
 
    LINES TERMINATED BY '
'

STORED AS SEQUENCEFILE;
-
--设置压缩类型为Gzip压缩

SET hive.exec.compress.output=true;

SET mapred.output.compress=true;

SET mapred.output.compression.codec=org.apache.hadoop.io.compress.GzipCodec;

--导入数据:

INSERT OVERWRITE TABLE student_seq_gzip SELECT * FROM student;

--查看数据

SELECT * FROM student_seq_gzip;

查看数据文件,是一个密文的文件,无法通过gzip解压:

hdfs dfs -ls /user/hive/warehouse/student_seq_gzip/
-rw-r--r--  /user/hive/warehouse/student_seq_gzip/000000_0

三、RCFILE

1、RCFILE,Gzip压缩

CREATE TABLE student_rcfile_gzip (id STRING, name STRING)

ROW FORMAT DELIMITED
 
    FIELDS TERMINATED BY ','
 
    LINES TERMINATED BY '
'

STORED AS RCFILE;



-
--设置压缩类型为Gzip压缩

SET hive.exec.compress.output=true;

SET mapred.output.compress=true;

SET mapred.output.compression.codec=org.apache.hadoop.io.compress.GzipCodec;

--导入数据:

INSERT OVERWRITE TABLE student_rcfile_gzip SELECT id,name FROM student;

--查看数据

SELECT * FROM student_rcfile_gzip;

四、ORCFile

ORCFile有自己的参数设置压缩格式,一般不使用上述Hive参数设置压缩参数。
参考文档:LanguageManual ORC(https://cwiki.apache.org/confluence/display/Hive/LanguageManual+ORC)

1、ORCFile,ZLIB压缩

--创建表

CREATE TABLE student_orcfile_zlib (id STRING, name STRING)

ROW FORMAT DELIMITED
 
    FIELDS TERMINATED BY ','
 
    LINES TERMINATED BY '
'

STORED AS ORCFILE TBLPROPERTIES ("orc.compress"="ZLIB");



-
--导入数据

INSERT OVERWRITE TABLE student_orcfile_zlib SELECT id,name FROM student;

--查询数据

SELECT * FROM student_orcfile_zlib;

2、ORCFILE,Snappy压缩

--创建表
C
CREATE TABLE student_orcfile_snappy2 (id STRING, name STRING)

ROW FORMAT DELIMITED
 
    FIELDS TERMINATED BY ','

    LINES TERMINATED BY '
'

STORED AS ORCFILE TBLPROPERTIES ("orc.compress"="SNAPPY");



-
--导入数据
I
INSERT OVERWRITE TABLE student_orcfile_snappy2 SELECT id,name FROM student;

--查询数据

SELECT * FROM student_orcfile_snappy2;
create external table `cp_api_log`(`line` string)
partitioned by (`date` string)
row format serde 'com.cloudera.hive.serde.JSONSerDe' 
stored as orc tblproperties ("orc.compress"="SNAPPY")
location 'hdfs://hdfs://BigdataCluster/user/hive/warehouse/sm_data.db/ods/ods_cp_api'

一般不使用下述方式。下述方式压缩后,结果与上述同类型压缩(SNAPPY)不同。具体原因待进一步研究。

--创建表

CREATE TABLE student_orcfile_snappy (id STRING, name STRING)

ROW FORMAT DELIMITED

    FIELDS TERMINATED BY ','
 
    LINES TERMINATED BY '
'

STORED AS ORCFILE;

--设置压缩

SET hive.exec.compress.output=true;

SET mapred.compress.map.output=true;

SET mapred.output.compress=true;

SET mapred.output.compression=org.apache.hadoop.io.compress.SnappyCodec;

SET mapred.output.compression.codec=org.apache.hadoop.io.compress.SnappyCodec;

SET io.compression.codecs=org.apache.hadoop.io.compress.SnappyCodec;

--导入数据

INSERT OVERWRITE TABLE student_orcfile_snappy SELECT id,name FROM student;

--查询数据

SELECT * FROM student_orcfile_snappy;

五、Parquet

1、Parquet,Snappy压缩

--创建表
CREATE TABLE student_parquet_snappy (id STRING, name STRING)
ROW FORMAT DELIMITED
    FIELDS TERMINATED BY ','
    LINES TERMINATED BY '
'
STORED AS PARQUET;
--设置压缩
SET hive.exec.compress.output=true;
SET mapred.compress.map.output=true;
SET mapred.output.compress=true;
SET mapred.output.compression=org.apache.hadoop.io.compress.SnappyCodec;
SET mapred.output.compression.codec=org.apache.hadoop.io.compress.SnappyCodec;
SET io.compression.codecs=org.apache.hadoop.io.compress.SnappyCodec;
--导入数据
INSERT OVERWRITE TABLE student_parquet_snappy SELECT id,name FROM student;
--查询数据
SELECT * FROM student_parquet_snappy;

 

六、Avro

1、Avro,Snappy压缩

--创建表
CREATE TABLE student_avro_snappy (id STRING, name STRING)
ROW FORMAT DELIMITED
    FIELDS TERMINATED BY ','
    LINES TERMINATED BY '
'
STORED AS AVRO;
--设置压缩
SET hive.exec.compress.output=true;
SET mapred.compress.map.output=true;
SET mapred.output.compress=true;
SET mapred.output.compression=org.apache.hadoop.io.compress.SnappyCodec;
SET mapred.output.compression.codec=org.apache.hadoop.io.compress.SnappyCodec;
SET io.compression.codecs=org.apache.hadoop.io.compress.SnappyCodec;
--导入数据
INSERT OVERWRITE TABLE student_avro_snappy SELECT id,name FROM student;
--查询数据
SELECT * FROM student_avro_snappy;
原文地址:https://www.cnblogs.com/LIAOBO/p/13627715.html