Mohit, There is nothing wrong with the query. It seems (from the line below) that you are using a custom SerDe: org.apache.hadoop.hive.contrib.serde2.XmlInputFormat$XmlRecordReader.<init>(XmlInputFormat.java:76)
That seems to the causing the problem. You'd need to look into the input format's code to see what's going on. Mark On Mon, Dec 17, 2012 at 2:19 AM, Mohit Chaudhary01 <mohit_chaudhar...@infosys.com> wrote: > > I am using serde in hive to store data into hive table from xml file. > > Whenever I retrieve data using command select * from table it give all > records from table. > > > > But when I want to extract an individual column it gives error . > > Please Tell me how can I retrieve a single column from this table. > > > > This is the error when I try to extract a single column from hive serde table > . > > > > java.lang.RuntimeException: java.lang.reflect.InvocationTargetException > > at > org.apache.hadoop.hive.shims.Hadoop20SShims$CombineFileRecordReader.initNextRecordReader(Hadoop20SShims.java:306) > > at > org.apache.hadoop.hive.shims.Hadoop20SShims$CombineFileRecordReader.<init>(Hadoop20SShims.java:269) > > at > org.apache.hadoop.hive.shims.Hadoop20SShims$CombineFileInputFormatShim.getRecordReader(Hadoop20SShims.java:366) > > at > org.apache.hadoop.hive.ql.io.CombineHiveInputFormat.getRecordReader(CombineHiveInputFormat.java:413) > > at org.apache.hadoop.mapred.MapTask.runOldMapper(MapTask.java:371) > > at org.apache.hadoop.mapred.MapTask.run(MapTask.java:325) > > at org.apache.hadoop.mapred.Child$4.run(Child.java:270) > > at java.security.AccessController.doPrivileged(Native Method) > > at javax.security.auth.Subject.doAs(Subject.java:396) > > at > org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1127) > > at org.apache.hadoop.mapred.Child.main(Child.java:264) > > Caused by: java.lang.reflect.InvocationTargetException > > at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native > Method) > > at > sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39) > > at > sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27) > > at java.lang.reflect.Constructor.newInstance(Constructor.java:513) > > at > org.apache.hadoop.hive.shims.Hadoop20SShims$CombineFileRecordReader.initNextRecordReader(Hadoop20SShims.java:292) > > ... 10 more > > Caused by: java.lang.NullPointerException > > at > org.apache.hadoop.hive.contrib.serde2.XmlInputFormat$XmlRecordReader.<init>(XmlInputFormat.java:76) > > at > org.apache.hadoop.hive.contrib.serde2.XmlInputFormat.getRecordReader(XmlInputFormat.java:44) > > at > org.apache.hadoop.hive.ql.io.CombineHiveRecordReader.<init>(CombineHiveRecordReader.java:68) > > ... 15 more > > > > > > From: Nitin Pawar [mailto:nitinpawar...@gmail.com] > Sent: Monday, December 17, 2012 1:54 PM > To: user@hive.apache.org > Subject: Re: reg : reteriveing a single column from hive serde table > > > > select * will just hdfs cat your file > > > > when you are using serde, do you have column separator in place? if not can > you do select * from table limit 1 > > > > to get normally a single coulmn you should do select column from table where > column=value > > > > On Mon, Dec 17, 2012 at 1:51 PM, Mohit Chaudhary01 > <mohit_chaudhar...@infosys.com> wrote: > > Hi > > I am using serde in hive to store data into hive table from xml file. > > Whenever I retrieve data using command select * from table it give all > records from table. > > > > But when I want to extract an individual column it gives error . > > Please Tell me how can I retrieve a single column from this table. > > > > Thanks > > Mohit chaudhary > > **************** CAUTION - Disclaimer ***************** > > This e-mail contains PRIVILEGED AND CONFIDENTIAL INFORMATION intended solely > > for the use of the addressee(s). If you are not the intended recipient, please > > notify the sender by e-mail and delete the original message. Further, you are > not > > to copy, disclose, or distribute this e-mail or its contents to any other > person and > > any such actions are unlawful. This e-mail may contain viruses. Infosys has > taken > > every reasonable precaution to minimize this risk, but is not liable for any > damage > > you may sustain as a result of any virus in this e-mail. You should carry out > your > > own virus checks before opening the e-mail or attachment. Infosys reserves the > > right to monitor and review the content of all messages sent to or from this > e-mail > > address. Messages sent to or from this e-mail address may be stored on the > > Infosys e-mail system. > > ***INFOSYS******** End of Disclaimer ********INFOSYS*** > > > > > > -- > Nitin Pawar
