Redis is a NOSQL database written in C. The Remote Dictionary Server is a key-value data base whose the storage is in memory, then the write and read will fastest way, but which difference between Redis and Cache? What does happen when the database fall down? Will we lost the all informations?
The main goal of this article is talk about the Redis and show an open source project, the redis-...
on Aug 1, 2014
Using the Java 8 Date Time Classes with JPA!
With the Java 8 SE release, developers get a splendid new best-in-class Date-Time API. Wouldn't it be nice if you could use it with JPA? Not so fast. JPA and for that matter JDBC know nothing about the new classes, and if you use them in your entities, JPA will map them to BLOBs in your database by default. This happens in DDL or database creation, in...
on Jun 17, 2014
The columnar storage is good, especially when there are lots of tabular fields (this is quite common). In querying, the data to traverse is far less than that on the row storage. Less data to traverse brings less I/O workloads and higher query speed. However, the Hadoop application consumes most time on the hard disk I/O without columnar storage.
Both Hive and Impala support columnar storage, but...
on Jan 24, 2014
The data warehouse is essential to enterprise business intelligence, which accounts for a great part of the total enterprise cost. With the global data explosion in recent years, the business data volume grow significantly, posing a serious challenge for enterprise data warehouse to meet the diverse and complex business demands. More data, more data warehouse applications, more concurrent...
on Dec 11, 2013
Note this blog is obsolete, see https://www.manorrock.com/blog/ for the current blog
If you are having a problem with your JPA queries and you are trying to understand what SQL queries it actually sends below the covers you can configure the JPA runtime to show the actual SQL statements it sends over. How? Well for EclipseLink you would add the following to your persistence.xml file.
on Oct 27, 2013
In Java, implementing via SQL is a well-developed practice for database computation. However, the structured data is not only stored in the database, but also in the text, Excel, and XML files. Considering this, how to compute appropriately regarding the structured data from non-database files? This article raises 3 solutions for your reference: implement via Java API, convert to database...
on Aug 29, 2013
According to research, most complex report development work can be simplified by performing the data source computation in advance. For example, find out the clients who bought all products in the given list, and then present the details of these clients.
In developing such reports, it is the
on Aug 20, 2013
In report development, we may need to present the data from multiple databases in one report, such as data from MSSQL database for CRM and Oracle database for ERP. If the reporting tool like iReport only supports single data source, then we need to consolidate the multiple data sources into a single data source.
The Crystal, BIRT, and other so-called reporting tools for multiple data source can...
on Aug 6, 2013
The Browser Binding with a CMIS Repository
By Florian Müller, Jay Brown, and Jeff Potts, authors of
CMIS and Apache Chemistry in Action
A big part of the CMIS specification describes how the CMIS domain model is mapped to the bytes that are transferred. These mappings are called bindings. CMIS 1.0 defines two bindings, the Web Services...
on Jul 2, 2013
Pig from a Bird's Eyeview
by M. Tim Jones, author of Pig in Action
Today, we are being inundated with data. So much so, that IBM estimates that in 2012, 2.5 quintillion bytes of information are generated every day. That's a million trillion bytes of data, more data than we can fathom and considerably more than we can easily process. Online, every web-page we visit, every link we click, every...
on May 20, 2013
Domain Model Metadata
by Christian Bauer, Gavin King, and Gary Gregory, authors of Java Persistence with Hibernate, Second Edition
The Java Platform, Enterprise Edition (Java EE) standard solves the problem of leaky concerns with metadata as annotations in your code or as external XML descriptors. This approach allows the runtime container to implement predefined cross-cutting concerns—...
on Apr 9, 2013
The applications have grown together with the man dream to get more and more information, then more application have been emerging and the man had became hostage of the application.
For example we can recognized the evolution between man and machine:
In the first time: Many men to just one machine ( like mainframe's age) then one man to one machine ( in to Personal computer era) and...
on Mar 17, 2013
Spatial reference system: What is it?
by Regina O. Obe and Leo S. Hsu, authors of PostGIS in Action, Second Edition
The topic of spatial reference systems (SRS) is one of the more abstruse in GIS to understand. This is mainly due to the loose way in which people use the term spatial reference system and secondly to its unglamorous nature compared to other areas of GIS. If GIS is Disneyland,...
on Feb 13, 2013
Many of the Oracle Java development tutorials that access a database do so against the Oracle HR sample schema. See, for example, Developing Rich Web Applications With Oracle ADF. There are several approaches you can take to getting the sample schema installed in the Oracle Cloud, such as Using SQL Developer or JDeveloper as demonstrated in Shay's blog. In my case, we're going to run the SQL...
on Jan 17, 2013
The new version of Easy-Cassandra, the version 2.0.1, have launched, some news are:
Refactoring constructor on Session Factory
QueryBuilder (InsertBuilder, UpdateBuilder, DeleteBuilder, SelectBuilder and BatchBuilder)
Go faster both write and read
More supports to Spring-Data
As have an easier the configuration a Session Factory, it was made the ClustInformation, this...
on Feb 13, 2014
Spring is an open source framework whose goals is facilitate the Java developer's life, it began with dependency injection and nowadays works on many plug-ins. Plug-ins such Spring Social, to connects social media like twitter and facebbok, Spring security beyond control inversion. The goal of this post is talk about Spring Data working with Cassandra.
Spring Data does part of Spring plug-in,...
on Aug 25, 2013
Cassandra is an open source column oriented nosql database. It was born to solve problems with persistence and high performance. Cassandra has been used by many companies in many industries for a wide variety of use cases. In addition it has a strong and thriving community supporting it.
We will be having a special series of events throughout Brazil in the first week of September. Each day...
on Aug 21, 2013
The Foundations of Mobile First Design
by Matthew Carver, author of The Responsive Web
In this article from The Responsive Web, author Matthew Carver opens up a discussion of how to build a site for a mobile or small-screen device using a graphic design program, such as Photoshop.
Building a site in its smallest iteration first affords the designer a lot of opportunities. By starting in a...
on Nov 14, 2012
Natural User Interaction with Drag-and-Drop
by Rob Crowther, author of Hello! HTML5 and CSS3
on Oct 29, 2012
From 0 to First Hit with Grails Support
by Glen Smith and Peter Ledbrook, authors of Grails in Action, Second Edition
Grails is a next-generation Java web development framework that generates great developer productivity gains through the confluence of a dynamic language, a Convention over Configuration philosophy, powerfully pragmatic supporting tools, and an agile perspective drawn from the...
on Oct 25, 2012