Loading xml data into hive table :org.apache.hadoo

问题:

I'm trying to load XML data into Hive but I'm getting an error :

java.lang.RuntimeException: org.apache.hadoop.hive.ql.metadata.HiveException: Hive Runtime Error while processing row {"xmldata":""}

The xml file i have used is :

<?xml version="1.0" encoding="UTF-8"?>
<catalog>
<book>
  <id>11</id>
  <genre>Computer</genre>
  <price>44</price>
</book>
<book>
  <id>44</id>
  <genre>Fantasy</genre>
  <price>5</price>
</book>
</catalog>

The hive query i have used is :

1) Create TABLE xmltable(xmldata string) STORED AS TEXTFILE;
LOAD DATA lOCAL INPATH '/home/user/xmlfile.xml' OVERWRITE INTO TABLE xmltable;

2) CREATE VIEW xmlview (id,genre,price)
AS SELECT
xpath(xmldata, '/catalog[1]/book[1]/id'),
xpath(xmldata, '/catalog[1]/book[1]/genre'),
xpath(xmldata, '/catalog[1]/book[1]/price')
FROM xmltable;

3) CREATE TABLE xmlfinal AS SELECT * FROM xmlview;

4) SELECT * FROM xmlfinal WHERE id ='11

Till 2nd query everything is fine but when i executed the 3rd query it's giving me error:

The error is as below:

java.lang.RuntimeException: org.apache.hadoop.hive.ql.metadata.HiveException: Hive Runtime Error while processing row {"xmldata":"<?xml version=\"1.0\" encoding=\"UTF-8\"?>"}
    at org.apache.hadoop.hive.ql.exec.ExecMapper.map(ExecMapper.java:159)
    at org.apache.hadoop.mapred.MapRunner.run(MapRunner.java:50)
    at org.apache.hadoop.mapred.MapTask.runOldMapper(MapTask.java:417)
    at org.apache.hadoop.mapred.MapTask.run(MapTask.java:332)
    at org.apache.hadoop.mapred.Child$4.run(Child.java:268)
    at java.security.AccessController.doPrivileged(Native Method)
    at javax.security.auth.Subject.doAs(Subject.java:415)
    at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1438)
    at org.apache.hadoop.mapred.Child.main(Child.java:262)
 Caused by: org.apache.hadoop.hive.ql.metadata.HiveException: Hive Runtime Error    while processing row {"xmldata":"<?xml version=\"1.0\" encoding=\"UTF-8\"?>"}
    at org.apache.hadoop.hive.ql.exec.MapOperator.process(MapOperator.java:675)
    at org.apache.hadoop.hive.ql.exec

FAILED: Execution Error, return code 2 from org.apache.hadoop.hive.ql.exec.MapRedTask

So where it's going wrong? Also I'm using the proper xml file.

Thanks, Shree

回答1:

Reason for error :

1) case-1 : (your case) - xml content is being fed to hive as line by line.

input xml:

<?xml version="1.0" encoding="UTF-8"?>
<catalog>
<book>
  <id>11</id>
  <genre>Computer</genre>
  <price>44</price>
</book>
<book>
  <id>44</id>
  <genre>Fantasy</genre>
  <price>5</price>
</book>
</catalog>  

check in hive :

select count(*) from xmltable;  // return 13 rows - means each line in individual row with col xmldata  

Reason for err :

XML is being read as 13 pieces not at unified. so invalid XML

2) case-2 : xml content should be fed to hive as singleString - XpathUDFs works refer syntax : All functions follow the form: xpath_(xml_string, xpath_expression_string).* source

input.xml

<?xml version="1.0" encoding="UTF-8"?><catalog><book><id>11</id><genre>Computer</genre><price>44</price></book><book><id>44</id><genre>Fantasy</genre><price>5</price></book></catalog>

check in hive:

select count(*) from xmltable; // returns 1 row - XML is properly read as complete XML.

Means :

xmldata   = <?xml version="1.0" encoding="UTF-8"?><catalog><book> ...... </catalog>

then apply your xpathUDF like this

select xpath(xmldata, 'xpath_expression_string' ) from xmltable

回答2:

Find Jar here -- > Brickhouse ,

sample example here --> Example

similar example in stackoverflow - here

Solution:

--Load xml data to table
DROP table xmltable;
Create TABLE xmltable(xmldata string) STORED AS TEXTFILE;
LOAD DATA lOCAL INPATH '/home/vijay/data-input.xml' OVERWRITE INTO TABLE xmltable;

-- check contents
SELECT * from xmltable;

-- create view
Drop view  MyxmlView;
CREATE VIEW MyxmlView(id, genre, price) AS
SELECT
 xpath(xmldata, 'catalog/book/id/text()'),
 xpath(xmldata, 'catalog/book/genre/text()'),
 xpath(xmldata, 'catalog/book/price/text()')
FROM xmltable;

-- check view
SELECT id, genre,price FROM MyxmlView;


ADD jar /home/vijay/brickhouse-0.7.0-SNAPSHOT.jar;  --Add brickhouse jar 

CREATE TEMPORARY FUNCTION array_index AS 'brickhouse.udf.collect.ArrayIndexUDF';
CREATE TEMPORARY FUNCTION numeric_range AS 'brickhouse.udf.collect.NumericRange';

SELECT 
   array_index( id, n ) as my_id,
   array_index( genre, n ) as my_genre,
   array_index( price, n ) as my_price
from MyxmlView
lateral view numeric_range( size( id )) MyxmlView as n;

Output:

hive > SELECT
     >    array_index( id, n ) as my_id,
     >    array_index( genre, n ) as my_genre,
     >    array_index( price, n ) as my_price
     > from MyxmlView
     > lateral view numeric_range( size( id )) MyxmlView as n;
Automatically selecting local only mode for query
Total MapReduce jobs = 1
Launching Job 1 out of 1
Number of reduce tasks is set to 0 since there's no reduce operator
Execution log at: /tmp/vijay/.log
Job running in-process (local Hadoop)
Hadoop job information for null: number of mappers: 0; number of reducers: 0
2014-07-09 05:36:45,220 null map = 0%,  reduce = 0%
2014-07-09 05:36:48,226 null map = 100%,  reduce = 0%
Ended Job = job_local_0001
Execution completed successfully
Mapred Local Task Succeeded . Convert the Join into MapJoin
OK
my_id      my_genre      my_price
11      Computer        44
44      Fantasy 5

Time taken: 8.541 seconds, Fetched: 2 row(s)

Adding-more-info as requested by Question owner:

回答3:

First try to load file my add file path-to-file, that will solve your problem as It is solved in my case

回答4:

Oracle XML Extensions for Hive can be used to create Hive tables over XML like this. https://docs.oracle.com/cd/E54130_01/doc.26/e54142/oxh_hive.htm#BDCUG691

回答5:

then follow the below steps to get the solution as like as you want, just change the source data this

 <catalog><book><id>11</id><genre>Computer</genre><price>44</price></book></catalog>
<catalog><book><id>44</id><genre>Fantasy</genre><price>5</price></book></catalog> 

now try below steps:

select xpath(xmldata, '/catalog/book/id/text()')as id,
xpath(xmldata, '/catalog/book/genre/text()')as genre,
xpath(xmldata, '/catalog/book/price/text()')as price FROM xmltable;

now you will get ans as like this:

["11"] ["Computer"] ["44"]

["44"] ["Fantasy"] ["5"]

if you apply xapth_string, xpath_int, xpath_int udfs the you will get ans like

11 computer 44

44 Fantasy 5.

Thanks

回答6:

Also ensure that the XML file doesn't contain any empty spaces at the end of the last closing tag. In my case, the source file had one, and whenever I loaded the file into hive, my resulting table contained NULLS in them. So whenever I applied an xpath function, the result would have a few of these [] [] [] [] [] []

Although the xpath_string function worked, the xpath_double and xpath_int functions never did. It kept throwing this exception -

Diagnostic Messages for this Task:
java.lang.RuntimeException: org.apache.hadoop.hive.ql.metadata.HiveException: Hive Runtime Error while processing row {"line":""}