I have a CSV file with embedded commas that I want to drop in a Hive directory so my Hive table will immediately see the data. I don't wish to pre-process the data, and the data has some consecutive double quotes. e.g.:
"hi,there",999,""BROWN,FOX"","goodbye"
I know I need to create my table using the CSV SerDe, and I have:
ROW FORMAT SERDE 'org.apache.hadoop.hive.serde2.OpenCSVSerde'
WITH SERDEPROPERTIES (
"separatorChar" = ",",
"quoteChar" = "\"",
"escapeChar" = "\\"
)
STORED AS TEXTFILE
but when I select the data for this sample data, I get this:
hive> select * from my_table;
hi,there 999 "BROWN FOX" goodbye
instead of what I want:
hive> select * from my_table;
hi,there 999 "BROWN,FOX" goodbye
or even:
hive> select * from my_table;
hi,there 999 BROWN,FOX goodbye
How do I get Hive to consider double double-quotes as a single double-quote, or otherwise read this data the way I want? Can I do this without pre-processing the data? Thank you in advance.
Related
Impala version: impalad version 4.0.0.2022.0.11.0-122
I have a CSV in S3 that has a field with newlines in it but the field is wrapped in double quotes. I can see that the CSV ignores the newlines in the field correctly but when issuing the CREATE statement in Impala it takes the newline as an actual newline for the row instead of just inside the field value, and messes up the structure of the CSV being ingested.
What can I do to ensure that newlines inside field values, that are wrapped in double quotations in the Impala table, are ignored?
CSV:
SQL CREATE statement:
CREATE EXTERNAL TABLE IF NOT EXISTS schema_name.table_name (
`week` VARCHAR(10),
notes STRING,
)
ROW FORMAT DELIMITED FIELDS TERMINATED BY ','
-- ESCAPED BY '"' -- tried this, didn't work
STORED AS TEXTFILE
LOCATION 's3a://bucket_name/folder_name/'
TBLPROPERTIES("skip.header.line.count"="1")
-- Also tried this (get syntax error, also tried without ROW FORMAT keywords):
-- ROW FORMAT SERDE 'org.apache.hadoop.hive.serde2.OpenCSVSerde' WITH SERDEPROPERTIES ( "separatorChar" = ",", "quoteChar" = """ )
Table:
I have my data in CSV format in the below form:
Id -> tinyint
Name -> String
Id Name
1 Alex
2 Sam
When I export the CSV file to S3 and create an Athena table, the data transform into the following format.
Id Name
1 "Alex"
2 "Sam"
How do I get rid of the double quotes while creating the table?
Any help is appreciated.
By default if SerDe is not specified, Athena is using LasySimpleSerDe, it does not support quoted values and reads quotes as a part of value. If your CSV file contains quoted values, use OpenCSVSerde (specify correct separatorChar if it is not comma):
CREATE EXTERNAL TABLE mytable(
id tinyint,
Name string
)
ROW FORMAT SERDE 'org.apache.hadoop.hive.serde2.OpenCSVSerde'
WITH SERDEPROPERTIES (
'separatorChar' = ',',
'quoteChar' = '\"',
'escapeChar' = '\\'
)
LOCATION 's3://my-bucket/mytable/'
;
Read the manuals: https://docs.aws.amazon.com/athena/latest/ug/csv-serde.html
See also this answer about data types in OpenCSVSerDe
I have a csv file which has fields enclosed in double quotes. I created an Redshift external table over it using OpenCSVSerDe.
The issue is one of my rows in the file has a trailing space outside the double quotes. Something like this:
"name1" ,"123","something"
"name2","234","somethingelse"
Now a SELECT on the external table returning NULL in the first row for the first column.
123 something
name2 234 somethingelse
However, the S3 SELECT functionality is returning proper values as below:
name1 123 something
name2 234 somethingelse
Is there any property at the table level which i can use to properly retrieve the data or this is a limitation?
Table DDL:
CREATE EXTERNAL TABLE test_table
(
column1 varchar(50)
,column2 varchar(50)
,column3 varchar(100)
)
ROW FORMAT SERDE 'org.apache.hadoop.hive.serde2.OpenCSVSerde'
WITH SERDEPROPERTIES ('separatorChar' = ',') --checked with and without this
STORED AS textfile
LOCATION 's3://s3bucketlocation'
;
I'm trying to load the json data into hive table. This json data contains newline characters. When I try to load this json data into hive table, it is not inserting properly.
My hive table creation:
CREATE EXTERNAL TABLE serde_tab(
gender STRING, name STRING
)
ROW FORMAT SERDE 'org.openx.data.jsonserde.JsonSerDe'
LOCATION '/user/input/text' ;
My json data:
{"gender":"femal\ne","name":"xyz"}
My hive table data:
select * from serde_tab;
OK
serde_tab.gender serde_tab.name
femal
e xyz
Can anyone please help me out regarding the same ...
You can use regexp_replace function to replace \n with ''.
hive> select regexp_replace(string("femal\ne"),'\n','');
+---------+--+
| _c0 |
+---------+--+
| female |
+---------+--+
(or)
Write a shell script to replace all \n newline characters with emptyvalues ('').
I have a csv file which has contents like this.
"DepartmentID","Name","GroupName","ModifiedDate"
"1","Engineering","Research and Development","2008-04-30 00:00:00"
I have
create external table if not exists AdventureWorks2014.Department
(
DepartmentID smallint ,
Name string ,
GroupName string,
rate_code string,
ModifiedDate timestamp
)
ROW FORMAT DELIMITED FIELDS TERMINATED BY '","' lines terminated by '\n'
STORED AS TEXTFILE LOCATION 'wasb:///ds/Department' TBLPROPERTIES('skip.header.line.count'='1');`
And after loading the data
LOAD DATA INPATH 'wasb:///ds/Department.csv' INTO TABLE AdventureWorks2014.Department;
The data is not loaded.
select * from AdventureWorks2014.Department;
The above select returns nothing.
I think the double quotes around each fileds is the issue. Is there a way to load the data from such a file to hive tables, Without having to strip out the double quotes?
Try this (cellphone...)
create external table if not exists AdventureWorks2014.Department ( DepartmentID smallint , Name string , GroupName string, rate_code string, ModifiedDate timestamp )
ROW FORMAT SERDE 'org.apache.hadoop.hive.serde2.OpenCSVSerde'
STORED AS TEXTFILE
LOCATION 'wasb:///ds/Department'
** Limitation **
This SerDe treats all columns to be of type String. Even if you create a table with non-string column types using this SerDe, the DESCRIBE TABLE output would show string column type. The type information is retrieved from the SerDe. To convert columns to the desired type in a table, you can create a view over the table that does the CAST to the desired type.
https://cwiki.apache.org/confluence/display/Hive/CSV+Serde
FIELDS TERMINATED BY '","' is incorrect. Your fields are terminated by a , not ",". Change your DDL to FIELDS TERMINATED BY ','.
LOAD DATA LOCAL INPATH '/home/hadoop/hive/log_2013805_16210.log'into table_name