Suppose I have two entities, a post and a comment (in ColdFusion):
component persistent=” true” table=”post”
{
property name=”Id” fieldtype=”id”;
property name=”Comments” fieldtype=”one-to-
Category: Opensource
Open-source software (open-source) is a new term that is defined as software whose source code can be used by the public, and the use, modification, and distribution of this software are not restricted by licenses. Open source software is usually copyrighted, and its license may contain such restrictions: deliberate protection of its open source status, notice of authorship, or development control. “Open source” is being registered as a certification mark by public interest software organizations, which is also a means of creating a formal definition of open source.
Hadoop – HBase Oldwals: What is it, how can I clean it?
There is not enough space in our small hadoop cluster, so I am checking the disk usage on HDFS and I found that most of the space is occupied by the /hbase/oldWALs folder.
I have checked the
What is the problem with NHIBERNATE solves?
I have seen some jobs that require nhibernate knowledge, and a large number of problems on the stack. I found another problem, pointing to Summer Of NHibernate, and now I am watching the video. But
Hibernate uses @Dynamicinsert and @Dynamicupdate to generate dynamic SQL statements
In using Hibernate4 recently, I found two very mysterious annotations @DynamicInsert and @DynamicUpdate
If it is in the configuration file That is, dynamic-insert and dynamic-update
The
Hibernate – Desire to get the entire object tree in Grails
So I have some objects in the domain, and they have a hasMany relationship, as shown below
Class Car {
String name
SortedSet tires = [] as SortedSet
static hasMany = [tires: Tire]
}
Class
Hadoop – Apache Spark runs Spark-shell on Yarn error
I downloaded spark-2.1.0-bin-hadoop2.7.tgz from http://spark.apache.org/downloads.html. I have Hadoop HDFS and YARN with $ start-dfs.sh and $start-yarn.sh start. But running $spark-shell –master ya
GRAILS default Hibernate cache configuration
The Grails 2.0.0 reference manual shows the following as the default Hibernate cache configuration
hibernate {
cache.use_second_level_cache=true
cache.use_query_cache=true
cache.provider_c
HBase tutorial
Since 1970, relational databases have been used to solve problems related to data storage and maintenance. After the emergence of big data, many companies realized and benefited from processing big
HDFS java API TROUBLESHOOTING
Official document:
https://hadoop.apache.org/docs/r2.9.2/hadoop-project-dist/hadoop-common/SingleCluster.html
Configuration free Password login for communication between nameNode and dataNode
Complete distributed construction of HBase
Reading statement: The following content is a personal understanding based on online materials and work. If it is inappropriate, please correct me~~~Thank you< /strong> 1. HBase installation mode