Brief description of HDFS architecture
1. Introduction to HDFS
HDFS (Hadoop distributed File System): Hadoop distributed file system. It is developed based on the needs of streaming dat
Author: Simo
Hive Advanced Query 1
hadoop hive advanced query select basics 1.0 general query
1)select * from table_name< /p> 2)select * from table_name where name=’….’ limit 1;
1.1cte and nested query
1)with t a
Hibernate SQL query does not correctly map Boolean value?
Run the following through any SQL client
SELECT FALSE, TRUE; return
f, t But this SQL query:
SQLQuery qry = session.createSQLQuery(“SELECT FALSE, TRUE;”);
Object[] result = (Objec
Hadoop – SQOOP cannot be imported into form
I am running a command on sqoop
sqoop import –connect jdbc:mysql://localhost/hadoopguide – table widgets My sqoop version: Sqoop 1.4.4.2.0.6.1-101
Hadoop – Hadoop 2.2.0.2.0.6.0-101
Tak
Polymorphism ‘get’ uses hibernate, multi-one, inheritancetype.joined
I have something like this..
A car class, one seat with many seats. Seat has a subclass LeatherSeat.
public class Car {
private Seat seat;
…
@ManyToOne(fetch = FetchType.LAZY)
pub
Install Yarn live
[ Summary] I recently got an open source project on gayhub, so I am going to study the source code. Of course, the first step is to get the project up and running. Then I took a look at the technol
Hibernate – Delete the parent reference before deleting the entity (if any)
Before deleting an entity, you must delete the entity from its parent list and delete the parent entity from the entity itself.
Example (CMT in EJB) One-to-many from state to city:
publ
Hadoop – Apache ozie loading Sharelib failed
I got the following oozie.log:
org.apache.oozie.service.ServiceException: E0104: Could not fully initialize service [org.apache.oozie.service.ShareLibService], Not able to cache sharelib. An
His longeting some HBase useful tools and features
1. HBase stores pictures, documents and other byte stream content
https://issues.apache.org/jira/browse/HBASE-11339
2. Speed control of compact
https://issues.apache.org/jira/br
Hive – Hadoop merged file
I have run a map job with only 674 mappers, and hive has generated 674 .gz files, and I want to merge these files into 30-35 files. Pass Do not get the merged output, try the hive megre mapfilse at