Most viewed questions in Big Data Hadoop

+2 votes
11 answers

hadoop fs -put command?

Hi, You can create one directory in HDFS ...READ MORE

Mar 16, 2018 in Big Data Hadoop by nitinrawat895
• 11,380 points
104,976 views
0 votes
5 answers

What is the HDFS command to list all the files in HDFS according to the timestamp?

You can try filter using value in ...READ MORE

Dec 7, 2018 in Big Data Hadoop by Lenny
71,165 views
+11 votes
11 answers

Hadoop “Unable to load native-hadoop library for your platform” warning

modify the glibc version.CentOS provides safe softwares ...READ MORE

Sep 10, 2018 in Big Data Hadoop by bug_seeker
• 15,520 points
69,482 views
0 votes
11 answers

What is the default Namenode port of HDFS. Is it 8020 or 9000 or 50070?

8020/9000 hadoop namenode metadata port number. or ...READ MORE

Dec 31, 2018 in Big Data Hadoop by SM
59,861 views
0 votes
1 answer

ERROR 1142 (42000): SELECT command denied to user ''@'localhost' for table 'user'

Hey, This is a mysql command line error ...READ MORE

Jun 20, 2019 in Big Data Hadoop by Gitika
• 65,910 points
53,526 views
0 votes
1 answer

How to add column inside a table in Hive?

Hi, Yes, we can add column inside a ...READ MORE

May 15, 2019 in Big Data Hadoop by Gitika
• 65,910 points
50,172 views
+1 vote
12 answers

How to check size of HDFS directory?

It is the same syntax. Use the ...READ MORE

Jun 6, 2019 in Big Data Hadoop by Sowmya
46,072 views
0 votes
9 answers

Is there any way to check which Hadoop daemons are running?

use jps command, It will show all the running ...READ MORE

Dec 27, 2018 in Big Data Hadoop by Rakesh
• 160 points
45,423 views
+1 vote
1 answer

http://localhost:50070 not working in HADOOP

There are 2 case possible: 1. If you ...READ MORE

Apr 16, 2018 in Big Data Hadoop by nitinrawat895
• 11,380 points
38,920 views
0 votes
1 answer

How to uninstall Yarn?

This is maybe because you didn't use ...READ MORE

Feb 5, 2019 in Big Data Hadoop by Omkar
• 69,210 points
38,899 views
+2 votes
10 answers

Is there any difference between “hdfs dfs” and “hadoop fs” shell commands?

hadoop fs <args> fs is used for generic ...READ MORE

Mar 16, 2018 in Big Data Hadoop by anonymous
32,637 views
0 votes
13 answers

What is the difference between Hadoop/HDFS & HBase?

HDFS is a distributed file system whereas ...READ MORE

Apr 26, 2019 in Big Data Hadoop by Arihar
• 160 points
32,338 views
0 votes
1 answer

Copy files in different folders in Hadoop.

Hi@akhtar, You can use the cp command in ...READ MORE

Oct 1, 2020 in Big Data Hadoop by MD
• 95,440 points
31,611 views
0 votes
1 answer

ERROR 1227 (42000): Access denied; you need (at least one of) the CREATE USER privilege(s) for this operation.

Hi, You can follow some steps to remove ...READ MORE

Jun 19, 2019 in Big Data Hadoop by Gitika
• 65,910 points
29,993 views
+1 vote
1 answer

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

Hi@akhtar, This issue generally occurs when the memory ...READ MORE

Apr 17, 2020 in Big Data Hadoop by MD
• 95,440 points
29,833 views
+1 vote
3 answers

What is the best way to merge multi-part HDFS files into single file?

1. In order to merge two or ...READ MORE

Jul 29, 2019 in Big Data Hadoop by Tina
29,751 views
0 votes
1 answer

How can you change a column data type in Hive?

Hi, By using this command below one can ...READ MORE

Jun 24, 2019 in Big Data Hadoop by Gitika
• 65,910 points
29,687 views
0 votes
1 answer

Installing Zookeeper on Windows

Follow the below-mentioned steps to install Zookeeper ...READ MORE

Feb 22, 2019 in Big Data Hadoop by Omkar
• 69,210 points
28,878 views
0 votes
1 answer

How to groupBy/count then filter on count in Scala

I think the exception is caused because ...READ MORE

Apr 19, 2018 in Big Data Hadoop by kurt_cobain
• 9,390 points
28,841 views
0 votes
12 answers

What is Zookeeper? What is the purpose of Zookeeper in Hadoop Ecosystem?

Hey, Apache Zookeeper says that it is a ...READ MORE

Apr 29, 2019 in Big Data Hadoop by Gitika
• 65,910 points
28,450 views
0 votes
1 answer

Replace Column names and datatype in Hive

You can replace the column name and ...READ MORE

May 21, 2019 in Big Data Hadoop by John
27,343 views
0 votes
1 answer

How to count lines in a file on hdfs command?

Use the below commands: Total number of files: hadoop ...READ MORE

Aug 10, 2018 in Big Data Hadoop by Neha
• 6,300 points
27,157 views
0 votes
1 answer

Bucketing vs Partitioning in HIve

Partition divides large amount of data into ...READ MORE

Jul 9, 2018 in Big Data Hadoop by Data_Nerd
• 2,390 points
26,542 views
+1 vote
1 answer

How to limit the number of rows per each item in a Hive QL?

SELECT a_id, b, c, count(*) as sumrequests FROM ...READ MORE

Dec 1, 2018 in Big Data Hadoop by Omkar
• 69,210 points
26,034 views
0 votes
7 answers

How to run a jar file in hadoop?

I used this command to run my ...READ MORE

Dec 10, 2018 in Big Data Hadoop by Dasinto
25,653 views
0 votes
2 answers

hadoop copy a local file system folder to HDFS

There's a typo in your command: "hadopp". ...READ MORE

Feb 4, 2019 in Big Data Hadoop by Lohith
24,550 views
0 votes
1 answer

What is the use of fsimage in hadoop?

The NameNode stores modifications to the file ...READ MORE

Dec 21, 2018 in Big Data Hadoop by Omkar
• 69,210 points
24,042 views
0 votes
3 answers

What is Hive? Is Hive a database?

Hive is a data Warehouse infrastructure/system built ...READ MORE

Jul 1, 2019 in Big Data Hadoop by Ved Gupta
22,988 views
0 votes
1 answer

How to remove files from HDFS system?

Hi@akhtar, You will find rm command in your ...READ MORE

Oct 1, 2020 in Big Data Hadoop by MD
• 95,440 points
22,317 views
0 votes
2 answers

Function of “hadoop namenode -format” command

Namenode is the node in the Hadoop ...READ MORE

Feb 4, 2019 in Big Data Hadoop by Kanika
20,589 views
0 votes
1 answer

What is the default location of Hadoop log files & how can I change that location?

The default directory of Hadoop log file ...READ MORE

May 4, 2018 in Big Data Hadoop by Shubham
• 13,490 points
20,582 views
0 votes
11 answers

What is the command to start Job history server in Hadoop 2.x & how to get its UI?

mr-jobhistory-daemon. sh start historyserver READ MORE

Jul 24, 2019 in Big Data Hadoop by Lokesh Singh
19,759 views
+2 votes
5 answers

How to transpose/pivot data in hive?

Below is also a way for Pivot SELECT ...READ MORE

Oct 12, 2018 in Big Data Hadoop by Rahul
19,174 views
0 votes
2 answers

How to get column names from Hive table?

To get all the columns of a ...READ MORE

Jun 4, 2019 in Big Data Hadoop by anonymous

edited Jun 4, 2019 by Omkar 19,090 views
0 votes
2 answers

Difference between Hadoop 1 and 2

Hadoop V.1.x Components Apache Hadoop V.1.x has the ...READ MORE

Aug 28, 2018 in Big Data Hadoop by zombie
• 3,790 points
19,039 views
0 votes
1 answer

How do you find an HDFS path URL?

Hi@akhtar, The Hadoop configuration file is default located ...READ MORE

Feb 28, 2020 in Big Data Hadoop by MD
• 95,440 points
18,971 views
0 votes
1 answer

How to convert a string to timestamp with milliseconds in Hive?

 concatenation of substrings using the following code: select ...READ MORE

Oct 31, 2018 in Big Data Hadoop by Neha
• 6,300 points
18,717 views
+1 vote
1 answer

Can we use LIKE operator in Hive?

Hey, Yes, Hive supports LIKE operator, but it ...READ MORE

Jun 19, 2019 in Big Data Hadoop by Gitika
• 65,910 points
18,620 views
0 votes
10 answers

Difference between single node & pseudo-distributed mode in Hadoop?

Single node is used for debugging the ...READ MORE

Dec 7, 2018 in Big Data Hadoop by Mahisha
18,451 views
0 votes
1 answer

How to create a parquet table in hive and store data in it from a hive table?

Please use the code attached below for ...READ MORE

Jan 28, 2019 in Big Data Hadoop by Omkar
• 69,210 points
18,090 views
0 votes
5 answers

Hadoop hdfs: list all files in a directory and its subdirectories

Hi, You can try this command: hadoop fs -ls ...READ MORE

Aug 1, 2019 in Big Data Hadoop by Dinish
17,408 views
+2 votes
4 answers

Datanode process not running in Hadoop

Run the following commands: Stop-all.sh start-dfs.sh start-yarn.sh mr-jobhistory-daemon.sh ...READ MORE

Oct 25, 2018 in Big Data Hadoop by Anand
17,388 views
0 votes
1 answer

Hive: ParseException line 5:20 missing EOF at '.' near

In the stored as parameter, you have specified the ...READ MORE

Jul 11, 2019 in Big Data Hadoop by Kim
16,850 views
0 votes
1 answer

Writing File into HDFS using spark scala

The reason you are not able to ...READ MORE

Apr 6, 2018 in Big Data Hadoop by kurt_cobain
• 9,390 points
16,800 views
0 votes
1 answer

How to replace characters in string in hive?

You can do it using regexp_replace. This is ...READ MORE

Nov 30, 2018 in Big Data Hadoop by Omkar
• 69,210 points
16,772 views
0 votes
3 answers

Spark Scala: How to list all folders in directory

val spark = SparkSession.builder().appName("Demo").getOrCreate() val path = new ...READ MORE

Dec 5, 2018 in Big Data Hadoop by Mark
16,593 views
0 votes
1 answer

How to Access Hive via Python?

The easiest way is to use PyHive. To ...READ MORE

Oct 9, 2018 in Big Data Hadoop by Omkar
• 69,210 points
16,556 views
0 votes
1 answer

Copy file from HDFS to the local file system

There are two possible ways to copy ...READ MORE

Mar 27, 2018 in Big Data Hadoop by nitinrawat895
• 11,380 points
16,486 views
0 votes
1 answer

nodetool: Failed to connect to '127.0.0.1:7199' - ConnectException: 'Connection refused (Connection refused)'.

Hi@akhtar, To avoid this error, You have to ...READ MORE

Apr 1, 2020 in Big Data Hadoop by MD
• 95,440 points
16,461 views