从CSV创建表,其值包含用引号括起来的逗号
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我正在尝试使用我上传到HDFS目录的CSV在Impala中创建一个表。 CSV包含用引号括起来的逗号的值。
例:
1.66.96.0/19,"NTT Docomo,INC.","Ntt Docomo",9605,"NTT DOCOMO, INC."
1.66.128.0/17,"NTT Docomo,INC.","Ntt Docomo",9605,"NTT DOCOMO, INC."
1.67.0.0/17,"NTT Docomo,INC.","Ntt Docomo",9605,"NTT DOCOMO, INC."
1.67.128.0/18,"NTT Docomo,INC.","Ntt Docomo",9605,"NTT DOCOMO, INC."
1.67.192.0/19,"NTT Docomo,INC.","Ntt Docomo",9605,"NTT DOCOMO, INC."
Impala documentation说这可以用ESCAPED BY
条款解决。这是我目前的代码:
DROP TABLE IF EXISTS GeoIP2_ISP_Blocks_IPv4;
CREATE TABLE GeoIP2_ISP_Blocks_IPv4 (
network STRING
,isp STRING
,organization STRING
,autonomous_system_number STRING
,autonomous_system_organization STRING
)
ROW FORMAT DELIMITED FIELDS TERMINATED BY ',' ESCAPED BY '\'
LOCATION 'hdfs://.../GeoIP2_ISP_Blocks_IPv4/';
INVALIDATE METADATA GeoIP2_ISP_Blocks_IPv4;
LOAD DATA INPATH 'hdfs://.../GeoIP2_ISP_Blocks_IPv4/'
INTO TABLE GeoIP2_ISP_Blocks_IPv4;
我也尝试过使用ESCAPED BY '"'
条款。在这两种情况下,Impala都使用引号中的逗号并将其用作分隔符,将值拆分为两列。
有关如何修复代码的任何想法,以便不会发生这种情况?
编辑(6/9/2015)
所以,我根据@K S Nidhin和@JTUP的建议,经历了以下变化。但是,每个变体返回的结果与不使用SERDEPROPERTIES
运算符的查询返回相同的结果,逗号仍然导致值出现在错误的列中:
变化1
DROP TABLE IF EXISTS GeoIP2_ISP_Blocks_IPv4;
CREATE TABLE GeoIP2_ISP_Blocks_IPv4 (
network STRING
,isp STRING
,organization STRING
,autonomous_system_number STRING
,autonomous_system_organization STRING
)
ROW FORMAT DELIMITED FIELDS TERMINATED BY ','
WITH SERDEPROPERTIES ( "quoteChar" = "'", "escapeChar" = "\" )
LOCATION 'hdfs://.../GeoIP2_ISP_Blocks_IPv4/';
INVALIDATE METADATA GeoIP2_ISP_Blocks_IPv4;
LOAD DATA INPATH 'hdfs://.../GeoIP2_ISP_Blocks_IPv4/'
INTO TABLE GeoIP2_ISP_Blocks_IPv4;
变化2
DROP TABLE IF EXISTS GeoIP2_ISP_Blocks_IPv4;
CREATE TABLE GeoIP2_ISP_Blocks_IPv4 (
network STRING
,isp STRING
,organization STRING
,autonomous_system_number STRING
,autonomous_system_organization STRING
)
ROW FORMAT DELIMITED FIELDS TERMINATED BY ',' ESCAPED BY '\'
WITH SERDEPROPERTIES ( 'quoteChar' = '"', 'escapeChar' = '\' )
LOCATION 'hdfs://.../GeoIP2_ISP_Blocks_IPv4/';
INVALIDATE METADATA GeoIP2_ISP_Blocks_IPv4;
LOAD DATA INPATH 'hdfs://.../GeoIP2_ISP_Blocks_IPv4/'
INTO TABLE GeoIP2_ISP_Blocks_IPv4;
变化3
DROP TABLE IF EXISTS GeoIP2_ISP_Blocks_IPv4;
CREATE TABLE GeoIP2_ISP_Blocks_IPv4 (
network STRING
,isp STRING
,organization STRING
,autonomous_system_number STRING
,autonomous_system_organization STRING
)
ROW FORMAT DELIMITED FIELDS TERMINATED BY ',' ESCAPED BY '\'
WITH SERDEPROPERTIES (
"separatorChar" = ",",
"quoteChar" = """
)
LOCATION 'hdfs://.../GeoIP2_ISP_Blocks_IPv4/';
INVALIDATE METADATA GeoIP2_ISP_Blocks_IPv4;
LOAD DATA INPATH 'hdfs://.../GeoIP2_ISP_Blocks_IPv4/'
INTO TABLE GeoIP2_ISP_Blocks_IPv4;
还有其他想法,还是SERDEPROPERTIES
运营商的进一步变化?
编辑(2016年10月6日)
我能够使用SERDE
和SERDEPROPERTIES
运算符在Hive中工作(基于Hive Documentation中提供的代码),并使用正确的表创建查询的不同变体:
DROP TABLE IF EXISTS GeoIP2_ISP_Blocks_IPv4;
CREATE TABLE GeoIP2_ISP_Blocks_IPv4(network STRING
,isp STRING
,organization STRING
,autonomous_system_number STRING
,autonomous_system_organization STRING)
ROW FORMAT SERDE 'org.apache.hadoop.hive.serde2.OpenCSVSerde'
WITH SERDEPROPERTIES (
'separatorChar' = ',',
'quoteChar' = '"',
'escapeChar' = '\'
)
STORED AS TEXTFILE;
LOAD DATA INPATH 'hdfs://.../GeoIP2_ISP_Blocks_IPv4/'
INTO TABLE GeoIP2_ISP_Blocks_IPv4;
由于在Impala中没有SERDE
运算符,因此该解决方案无法在那里运行。我很好在Hive中创建表格,但我仍然无法在Impala中找到可行的解决方案。
DROP TABLE IF EXISTS GeoIP2_ISP_Blocks_IPv4;
CREATE TABLE GeoIP2_ISP_Blocks_IPv4 (
network STRING
,isp STRING
,organization STRING
,autonomous_system_number STRING
,autonomous_system_organization STRING
)
ROW FORMAT DELIMITED FIELDS TERMINATED BY ',' ESCAPED BY '\'
WITH SERDEPROPERTIES (
"separatorChar" = ",",
"quoteChar" = """
)
LOCATION 'hdfs://.../GeoIP2_ISP_Blocks_IPv4/';
INVALIDATE METADATA GeoIP2_ISP_Blocks_IPv4;
LOAD DATA INPATH 'hdfs://.../GeoIP2_ISP_Blocks_IPv4/'
INTO TABLE GeoIP2_ISP_Blocks_IPv4;
添加SERDEPROPERTIES,希望可以做到这一点
我所做的是首先将分隔符从逗号转换为其他字符,例如pipe('|')。你可以在linux上使用csvformat(csvkit的一部分)。
csvformat -D | input_filename.csv > input_filename-pipe.csv
之后,将分隔符设置为“|”在impala查询中
TERMINATED BY '|'
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