Why big IT projects always go wrong In 1975, a computer scientist named Fred Brooks published one of the seminal texts in the literature of computing. It had the intriguing title of The Mythical Man-Month and it consisted simply of a set of essays on the art of managing large software projects. Between its covers is distilled more wisdom about computing than is contained in any other volume, which is why it has never been out of print.
Derby 10.5 preview: In-memory backend : Knut Anders Hatlen's Web The upcoming Derby 10.5 release will contain a long-awaited feature: an in-memory storage backend. With this backend, your entire database will be stored in main memory instead of on disk. But isn't the whole point of using a database that the data should be stored safely on disk or some other kind of persistent storage? Normally, yes, but there are cases where you don't really care if you lose the database when the application crashes. For instance, if you are running unit tests against your application, it's probably more important that the tests run fast and that it's easy to clean up after the tests.
ACID According to Gray and Reuter, IMS supported ACID transactions in 1973 already (although the term ACID came later). Characteristics The characteristics of these four properties as defined by Reuter and Härder are as follows: Atomicity The MongoDB Blog This is part 2 of a series, with part 1 covering the bare essentials to get you going. In this post we are going to take a closer look at queries and how indexes work in MongoDB. Introduction
What is Linked Data Level: introductory In the early 1990s there began to emerge a new way of using the internet to link documents together. It was called the World Wide Web. What the Web did that was fundamentally new was that it enabled people to publish documents on the internet and link them such that you could navigate from one document to another. Part of Sir Tim Berners-Lee’s original vision of the Web was that it should also be used to publish, share and link data.
Google’s HTML5 Web Designer Gets Animation Tools, Deeper AdWords And DoubleClick Integrations Last September, Google launched Web Designer, a free tool for Mac, Windows and Linux that makes it easy for anybody to build interactive HTML5 sites and ads. Since its launch, Web Designer got a couple of minor updates, but today’s release is the first major update in a long time and brings quite a few new features to the software. The company says that ads built with Web Designer have now been seen over 2.5 billion times.
Performance Performance Comparison PolePosition Benchmark Database Performance Tuning Using the Built-In Profiler Application Profiling Database Profiling Statement Execution Plans How Data is Stored and How Indexes Work Fast Database Import Performance Comparison In many cases H2 is faster than other (open source and not open source) database engines. Why use a database instead of just saving your data to disk? This Q&A is part of a weekly series of posts highlighting common questions encountered by technophiles and answered by users at Stack Exchange, a free, community-powered network of 100+ Q&A sites. Dokkat appears to think that databases are overused. "Instead of a database, I just serialize my data to JSON, saving and loading it to disk when necessary," he writes. "All the data management is made on the program itself, which is faster AND easier than using SQL queries." What is missing here? Why should a developer use a database when saving data to a disk might work just as well?
PHP Libraries, Frameworks and Tools Doctrine ODM (Object Document Mapper) is an experimental Doctrine MongoDB object mapper. The Doctrine\ODM\Mongo namespace is an experimental project for a PHP 5.3 MongoDB Object Mapper. It allows you to easily write PHP 5 classes and map them to collections in MongoDB. You just work with your objects like normal and Doctrine will transparently persist them to MongoDB. Semantic Models for CDISC Kerstin Forsberg has written an article discussing a presentation she and Frederik Malfait gave regarding the use of semantic models for CDISC-based standard and metadata management, pointing to case studies at AstraZeneca and Roche. She writes, “In AstraZeneca we have a new program called Integrative Informatics (i2) establishing the components required to let a linked data cloud grow across R&D. A key component is the URI policy for how to make for example a Clinical Study linkable by giving it a URI, that is a Uniform Resource Identifier, e.g. This is an identifier for a clinical study with the study code D5890C00003 that should be persistent and not dependent on any system.
Google Opens Its Cloud Vision API To All Developers After a short limited preview, Google today announced the public beta of its Cloud Vision API — a service that allows developers to easily build image recognition and classification features into their applications. Google’s technology do basic things like extracting text from images, but its real power is in actually recognizing the objects in an image. This is the same technology that powers the image search in Google Photos and it can recognize anything from flowers, food and animals to local landmarks. Google says it has trained the algorithm to recognize “thousands” of different objects. Image classification is probably the most interesting feature in the API, but the service can also flag inappropriate content, for example, so if you want to keep your photo-centric app PG-rated, the Cloud Vision API can help you there, too.
SQL Tutorial - SQL Query Reference and Programming Examples SQL (Structured Query Language) is a computer language aimed to store, manipulate, and query data stored in relational databases. The first incarnation of SQL appeared in 1974, when a group in IBM developed the first prototype of a relational database. The first commercial relational database was released by Relational Software (later becoming Oracle). Standards for SQL exist.
DataStax Cassandra 1.2 Documentation An index is a data structure that allows for fast, efficient lookup of data matching a given condition. About primary indexes In relational database design, a primary key is the unique key used to identify each row in a table. A primary key index, like any index, speeds up random access to data in the table.