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• SQL SERVER – Integrate Your Data with Skyvia – Cloud ETL Solution

  - by Pinal Dave

  In our days data integration often becomes a key aspect of business success. For business analysts it’s very important to get integrated data from various sources, such as relational databases, cloud CRMs, etc. to make correct and successful decisions. There are various data integration solutions on market, and today I will tell about one of them – Skyvia. Skyvia is a cloud data integration service, which allows integrating data in cloud CRMs and different relational databases. It is a completely online solution and does not require anything except for a browser. Skyvia provides powerful etl tools for data import, export, replication, and synchronization for SQL Server and other databases and cloud CRMs. You can use Skyvia data import tools to load data from various sources to SQL Server (and SQL Azure). Skyvia supports such cloud CRMs as Salesforce and Microsoft Dynamics CRM and such databases as MySQL and PostgreSQL. You even can migrate data from SQL Server to SQL Server, or from SQL Server to other databases and cloud CRMs. Additionally Skyvia supports import of CSV files, either uploaded manually or stored on cloud file storage services, such as Dropbox, Box, Google Drive, or FTP servers. When data import is not enough, Skyvia offers bidirectional data synchronization. With this tool, you can synchronize SQL Server data with other databases and cloud CRMs. After performing the first synchronization, Skyvia tracks data changes in the synchronized data storages. In SQL Server databases (and other relational databases) it creates additional tracking tables and triggers. This allows synchronizing only the changed data. Skyvia also maps records by their primary key values to each other, so it does not require different sources to have the same primary key structure. It still can match the corresponding records without having to add any additional columns or changing data structure. The only requirement for synchronization is that primary keys must be autogenerated. With Skyvia it’s not necessary for data to have the same structure in integrated data storages. Skyvia supports powerful mapping mechanisms that allow synchronizing data with completely different structure. It provides support for complex mathematical and string expressions when mapping data, using lookups, etc. You may use data splitting – loading data from a single CSV file or source table to multiple related target tables. Or you may load data from several source CSV files or tables to several related target tables. In each case Skyvia preserves data relations. It builds corresponding relations between the target data automatically. When you often work with cloud CRM data, native CRM data reporting and analysis tools may be not enough for you. And there is a vast set of professional data analysis and reporting tools available for SQL Server. With Skyvia you can quickly copy your cloud CRM data to an SQL Server database and apply corresponding SQL Server tools to the data. In such case you can use Skyvia data replication tools. It allows you to quickly copy cloud CRM data to SQL Server or other databases without customizing any mapping. You need just to specify columns to copy data from. Target database tables will be created automatically. Skyvia offers powerful filtering settings to replicate only the records you need. Skyvia also provides capability to export data from SQL Server (including SQL Azure) and other databases and cloud CRMs to CSV files. These files can be either downloadable manually or loaded to cloud file storages or FTP server. You can use export, for example, to backup SQL Azure data to Dropbox. Any data integration operation can be scheduled for automatic execution. Thus, you can automate your SQL Azure data backup or data synchronization – just configure it once, then schedule it, and benefit from automatic data integration with Skyvia. Currently registration and using Skyvia is completely free, so you can try it yourself and find out whether its data migration and integration tools suits for you. Visit this link to register on Skyvia: https://app.skyvia.com/register Reference: Pinal Dave (http://blog.sqlauthority.com)Filed under: PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL Tagged: Cloud Computing

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• Oracle Big Data Software Downloads

  - by Mike.Hallett(at)Oracle-BI&EPM

  Companies have been making business decisions for decades based on transactional data stored in relational databases. Beyond that critical data, is a potential treasure trove of less structured data: weblogs, social media, email, sensors, and photographs that can be mined for useful information. Oracle offers a broad integrated portfolio of products to help you acquire and organize these diverse data sources and analyze them alongside your existing data to find new insights and capitalize on hidden relationships. Oracle Big Data Connectors Downloads here, includes: Oracle SQL Connector for Hadoop Distributed File System Release 2.1.0 Oracle Loader for Hadoop Release 2.1.0 Oracle Data Integrator Companion 11g Oracle R Connector for Hadoop v 2.1 Oracle Big Data Documentation The Oracle Big Data solution offers an integrated portfolio of products to help you organize and analyze your diverse data sources alongside your existing data to find new insights and capitalize on hidden relationships. Oracle Big Data, Release 2.2.0 - E41604_01 zip (27.4 MB) Integrated Software and Big Data Connectors User's Guide HTML PDF Oracle Data Integrator (ODI) Application Adapter for Hadoop Apache Hadoop is designed to handle and process data that is typically from data sources that are non-relational and data volumes that are beyond what is handled by relational databases. Typical processing in Hadoop includes data validation and transformations that are programmed as MapReduce jobs. Designing and implementing a MapReduce job usually requires expert programming knowledge. However, when you use Oracle Data Integrator with the Application Adapter for Hadoop, you do not need to write MapReduce jobs. Oracle Data Integrator uses Hive and the Hive Query Language (HiveQL), a SQL-like language for implementing MapReduce jobs. Employing familiar and easy-to-use tools and pre-configured knowledge modules (KMs), the application adapter provides the following capabilities: Loading data into Hadoop from the local file system and HDFS Performing validation and transformation of data within Hadoop Loading processed data from Hadoop to an Oracle database for further processing and generating reports Oracle Database Loader for Hadoop Oracle Loader for Hadoop is an efficient and high-performance loader for fast movement of data from a Hadoop cluster into a table in an Oracle database. It pre-partitions the data if necessary and transforms it into a database-ready format. Oracle Loader for Hadoop is a Java MapReduce application that balances the data across reducers to help maximize performance. Oracle R Connector for Hadoop Oracle R Connector for Hadoop is a collection of R packages that provide: Interfaces to work with Hive tables, the Apache Hadoop compute infrastructure, the local R environment, and Oracle database tables Predictive analytic techniques, written in R or Java as Hadoop MapReduce jobs, that can be applied to data in HDFS files You install and load this package as you would any other R package. Using simple R functions, you can perform tasks such as: Access and transform HDFS data using a Hive-enabled transparency layer Use the R language for writing mappers and reducers Copy data between R memory, the local file system, HDFS, Hive, and Oracle databases Schedule R programs to execute as Hadoop MapReduce jobs and return the results to any of those locations Oracle SQL Connector for Hadoop Distributed File System Using Oracle SQL Connector for HDFS, you can use an Oracle Database to access and analyze data residing in Hadoop in these formats: Data Pump files in HDFS Delimited text files in HDFS Hive tables For other file formats, such as JSON files, you can stage the input in Hive tables before using Oracle SQL Connector for HDFS. Oracle SQL Connector for HDFS uses external tables to provide Oracle Database with read access to Hive tables, and to delimited text files and Data Pump files in HDFS. Related Documentation Cloudera's Distribution Including Apache Hadoop Library HTML Oracle R Enterprise HTML Oracle NoSQL Database HTML Recent Blog Posts Big Data Appliance vs. DIY Price Comparison Big Data: Architecture Overview Big Data: Achieve the Impossible in Real-Time Big Data: Vertical Behavioral Analytics Big Data: In-Memory MapReduce Flume and Hive for Log Analytics Building Workflows in Oozie

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• Q&A: Oracle's Paul Needham on How to Defend Against Insider Attacks

  - by Troy Kitch

  Source: Database Insider Newsletter: The threat from insider attacks continues to grow. In fact, just since January 1, 2014, insider breaches have been reported by a major consumer bank, a major healthcare organization, and a range of state and local agencies, according to the Privacy Rights Clearinghouse.  We asked Paul Needham, Oracle senior director, product management, to shed light on the nature of these pernicious risks—and how organizations can best defend themselves against the threat from insider risks. Q. First, can you please define the term "insider" in this context? A. According to the CERT Insider Threat Center, a malicious insider is a current or former employee, contractor, or business partner who "has or had authorized access to an organization's network, system, or data and intentionally exceeded or misused that access in a manner that negatively affected the confidentiality, integrity, or availability of the organization's information or information systems."  Q. What has changed with regard to insider risks? A. We are actually seeing the risk of privileged insiders growing. In the latest Independent Oracle Users Group Data Security Survey, the number of organizations that had not taken steps to prevent privileged user access to sensitive information had grown from 37 percent to 42 percent. Additionally, 63 percent of respondents say that insider attacks represent a medium-to-high risk—higher than any other category except human error (by an insider, I might add). Q. What are the dangers of this type of risk? A. Insiders tend to have special insight and access into the kinds of data that are especially sensitive. Breaches can result in long-term legal issues and financial penalties. They can also damage an organization's brand in a way that directly impacts its bottom line. Finally, there is the potential loss of intellectual property, which can have serious long-term consequences because of the loss of market advantage.  Q. How can organizations protect themselves against abuse of privileged access? A. Every organization has privileged users and that will always be the case. The questions are how much access should those users have to application data stored in the database, and how can that default access be controlled? Oracle Database Vault (See image) was designed specifically for this purpose and helps protect application data against unauthorized access.  Oracle Database Vault can be used to block default privileged user access from inside the database, as well as increase security controls on the application itself. Attacks can and do come from inside the organization, and they are just as likely to come from outside as attempts to exploit a privileged account.  Using Oracle Database Vault protection, boundaries can be placed around database schemas, objects, and roles, preventing privileged account access from being exploited by hackers and insiders.  A new Oracle Database Vault capability called privilege analysis identifies privileges and roles used at runtime, which can then be audited or revoked by the security administrators to reduce the attack surface and increase the security of applications overall.  For a more comprehensive look at controlling data access and restricting privileged data in Oracle Database, download Needham's new e-book, Securing Oracle Database 12c: A Technical Primer. 

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• SQL SERVER – A Puzzle – Swap Value of Column Without Case Statement

  - by pinaldave

  For the last few weeks, I have been doing Friday Puzzles and I am really loving it. Yesterday I received a very interesting question by Navneet Chaurasia on Facebook Page. He was asked this question in one of the interview questions for job. Please read the original thread for a complete idea of the conversation. I am presenting the same question here. Puzzle Let us assume there is a single column in the table called Gender. The challenge is to write a single update statement which will flip or swap the value in the column. For example if the value in the gender column is ‘male’ swap it with ‘female’ and if the value is ‘female’ swap it with ‘male’. Here is the quick setup script for the puzzle. USE tempdb GO CREATE TABLE SimpleTable (ID INT, Gender VARCHAR(10)) GO INSERT INTO SimpleTable (ID, Gender) SELECT 1, 'female' UNION ALL SELECT 2, 'male' UNION ALL SELECT 3, 'male' GO SELECT * FROM SimpleTable GO The above query will return following result set. The puzzle was to write a single update column which will generate following result set. There are multiple answers to this simple puzzle. Let me show you three different ways. I am assuming that the column will have either value ‘male’ or ‘female’ only. Method 1: Using CASE Statement I believe this is going to be the most popular solution as we are all familiar with CASE Statement. UPDATE SimpleTable SET Gender = CASE Gender WHEN 'male' THEN 'female' ELSE 'male' END GO SELECT * FROM SimpleTable GO Method 2: Using REPLACE  Function I totally understand it is the not cleanest solution but it will for sure work in giving situation. UPDATE SimpleTable SET Gender = REPLACE(('fe'+Gender),'fefe','') GO SELECT * FROM SimpleTable GO Method 3: Using IIF in SQL Server 2012 If you are using SQL Server 2012 you can use IIF and get the same effect as CASE statement. UPDATE SimpleTable SET Gender = IIF(Gender = 'male', 'female', 'male') GO SELECT * FROM SimpleTable GO You can read my article series on SQL Server 2012 various functions over here. SQL SERVER – Denali – Logical Function – IIF() – A Quick Introduction SQL SERVER – Detecting Leap Year in T-SQL using SQL Server 2012 – IIF, EOMONTH and CONCAT Function Let us clean up. DROP TABLE SimpleTable GO Question to you: I came up with three simple tricks where there is a single UPDATE statement which swaps the values in the column. Do you know any other simple trick? If yes, please post here in the comments. I will pick two random winners from all the valid answers. Winners will get 1) Print Copy of SQL Server Interview Questions and Answers 2) Free Learning Code for Online Video Courses I will announce the winners on coming Monday. Reference:  Pinal Dave (http://blog.SQLAuthority.com) Filed under: CodeProject, PostADay, SQL, SQL Authority, SQL Interview Questions and Answers, SQL Puzzle, SQL Query, SQL Server, SQL Tips and Tricks, SQLServer, T SQL, Technology

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• Archiving SQLHelp tweets

  - by jamiet

  #SQLHelp is a Twitter hashtag that can be used by any Twitter user to get help from the SQL Server community. I think its fair to say that in its first year of being it has proved to be a very useful resource however Kendra Little (@kendra_little) made a very salient point yesterday when she tweeted: Is there a way to search the archives of #sqlhelp Trying to remember answer to a question I know I saw a couple months ago http://twitter.com/#!/Kendra_Little/status/15538234184441856 This highlights an inherent problem with Twitter’s search capability – it simply does not reach far enough back in time. I have made steps to remedy that situation by putting into place two initiatives to archive Tweets that contain the #sqlhelp hashtag. The Archivist http://archivist.visitmix.com/ is a free service that, quite simply, archives a history of tweets that contain a given search term by periodically polling Twitter’s search service with that search term and subsequently displaying a dashboard providing an aggregate view of those tweets for things like tweet volume over time, top users and top words (Archivist FAQ). I have set up an archive on The Archivist for “sqlhelp” which you can view at http://archivist.visitmix.com/jamiet/7. Here is a screenshot of the SQLHelp dashboard 36 minutes after I set it up: There is lots of good information in there, including the fact that Jonathan Kehayias (@SQLSarg) is the most active SQLHelp tweeter (I suspect as an answerer rather than a questioner ) and that SSIS has proven to be a rather (ahem) popular subject!! Datasift The Archivist has its uses though for our purposes it has a couple of downsides. For starters you cannot search through an archive (which is what Kendra was after) and nor can you export the contents of the archive for offline analysis. For those functions we need something a bit more heavyweight and for that I present to you Datasift. Datasift is a tool (currently an alpha release) that allows you to search for tweets and provide them through an object called a Datasift stream. That sounds very similar to normal Twitter search though it has one distinct advantage that other Twitter search tools do not – Datasift has access to Twitter’s Streaming API (aka the Twitter Firehose). In addition it has access to a lot of other rather nice features: It provides the Datasift API that allows you to consume the output of a Datasift stream in your tool of choice (bring on my favourite ultimate mashup tool J ) It has a query language (called Filtered Stream Definition Language – FSDL for short) A Datasift stream can consume (and filter) other Datasift streams Datasift can (and does) consume services other than Twitter If I refer to Datasift as “ETL for tweets” then you may get some sort of idea what it is all about. Just as I did with The Archivist I have set up a publicly available Datasift stream for “sqlhelp” at http://datasift.net/stream/1581/sqlhelp. Here is the FSDL query that provides the data: twitter.text contains "sqlhelp" Pretty simple eh? At the current time it provides little more than a rudimentary dashboard but as Datasift is currently an alpha release I think this may be worth keeping an eye on. The real value though is the ability to consume the output of a stream via Datasift’s RESTful API, observe: http://api.datasift.net/stream.xml?stream_identifier=c7015255f07e982afdeebdf1ae6e3c0d&username=jamiet&api_key=XXXXXXX (Note that an api_key is required during the alpha period so, given that I’m not supplying my api_key, this URI will not work for you) Just to prove that a Datasift stream can indeed consume data from another stream I have set up a second stream that further filters the first one for tweets containing “SSIS”. That one is at http://datasift.net/stream/1586/ssis-sqlhelp and here is the FSDL query: rule "414c9845685ff8d2548999cf3162e897" and (interaction.content contains "ssis") When Datasift moves beyond alpha I’ll re-assess how useful this is going to be and post a follow-up blog. @Jamiet

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• SQL SERVER – Expanding Views – Contest Win Joes 2 Pros Combo (USD 198) – Day 4 of 5

  - by pinaldave

  August 2011 we ran a contest where every day we give away one book for an entire month. The contest had extreme success. Lots of people participated and lots of give away. I have received lots of questions if we are doing something similar this month. Absolutely, instead of running a contest a month long we are doing something more interesting. We are giving away USD 198 worth gift every day for this week. We are giving away Joes 2 Pros 5 Volumes (BOOK) SQL 2008 Development Certification Training Kit every day. One copy in India and One in USA. Total 2 of the giveaway (worth USD 198). All the gifts are sponsored from the Koenig Training Solution and Joes 2 Pros. The books are available here Amazon | Flipkart | Indiaplaza How to Win: Read the Question Read the Hints Answer the Quiz in Contact Form in following format Question Answer Name of the country (The contest is open for USA and India residents only) 2 Winners will be randomly selected announced on August 20th. Question of the Day: Which of the following key word will force the query to use indexes created on views? a) ENCRYPTION b) SCHEMABINDING c) NOEXPAND d) CHECK OPTION Query Hints: BIG HINT POST Usually, the assumption is that Index on the table will use Index on the table and Index on view will be used by view. However, that is the misconception. It does not happen this way. In fact, if you notice the image, you will find the both of them (table and view) use both the index created on the table. The index created on the view is not used. The reason for the same as listed in BOL. The cost of using the indexed view may exceed the cost of getting the data from the base tables, or the query is so simple that a query against the base tables is fast and easy to find. This often happens when the indexed view is defined on small tables. You can use the NOEXPAND hint if you want to force the query processor to use the indexed view. This may require you to rewrite your query if you don’t initially reference the view explicitly. You can get the actual cost of the query with NOEXPAND and compare it to the actual cost of the query plan that doesn’t reference the view. If they are close, this may give you the confidence that the decision of whether or not to use the indexed view doesn’t matter. Additional Hints: I have previously discussed various concepts from SQL Server Joes 2 Pros Volume 4. SQL Joes 2 Pros Development Series – Structured Error Handling SQL Joes 2 Pros Development Series – SQL Server Error Messages SQL Joes 2 Pros Development Series – Table-Valued Functions SQL Joes 2 Pros Development Series – Table-Valued Store Procedure Parameters SQL Joes 2 Pros Development Series – Easy Introduction to CHECK Options SQL Joes 2 Pros Development Series – Introduction to Views SQL Joes 2 Pros Development Series – All about SQL Constraints Next Step: Answer the Quiz in Contact Form in following format Question Answer Name of the country (The contest is open for USA and India) Bonus Winner Leave a comment with your favorite article from the “additional hints” section and you may be eligible for surprise gift. There is no country restriction for this Bonus Contest. Do mention why you liked it any particular blog post and I will announce the winner of the same along with the main contest. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: Joes 2 Pros, PostADay, SQL, SQL Authority, SQL Puzzle, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology

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• Autoscaling in a modern world&hellip;. last chapter

  - by Steve Loethen

  As we all know as coders, things like logging are never important.  Our code will work right the first time.  So, you can understand my surprise when the first time I deployed the autoscaling worker role to the actual Azure fabric, it did not scale.  I mean, it worked on my machine.  How dare the datacenter argue with that.  So, how did I track down the problem?  (turns out, it was not so much code as lack of the right certificate)  When I ran it local in the developer fabric, I was able to see a wealth of information.  Lots of periodic status info every time the autoscalar came around to check on my rules and decide to act or not.  But that information was not making it to Azure storage.  The diagnostics were not being transferred to where I could easily see and use them to track down why things were not being cooperative.  After a bit of digging, I discover the problem.  You need to add a bit of extra configuration code to get the correct information stored for you.  I added the following to my app.config: Code Snippet <system.diagnostics>     <sources>         <source name="Autoscaling General"switchName="SourceSwitch"           switchType="System.Diagnostics.SourceSwitch" >         <listeners>           <add name="AzureDiag" />             <remove name="Default"/>         </listeners>       </source>         <source name="Autoscaling Updates"switchName="SourceSwitch"           switchType="System.Diagnostics.SourceSwitch" >         <listeners>           <add name="AzureDiag" />             <remove name="Default"/>         </listeners>       </source>     </sources>     <switches>       <add name="SourceSwitch"           value="Verbose, Information, Warning, Error, Critical" />     </switches>     <sharedListeners>       <add type="Microsoft.WindowsAzure.Diagnostics.DiagnosticMonitorTraceListener,Microsoft.WindowsAzure.Diagnostics, Version=1.0.0.0, Culture=neutral,PublicKeyToken=31bf3856ad364e35" name="AzureDiag"/>     </sharedListeners>     <trace>       <listeners>         <add             type="Microsoft.WindowsAzure.Diagnostics.DiagnosticMonitorTraceListener,Microsoft.WindowsAzure.Diagnostics, Version=1.0.0.0, Culture=neutral,PublicKeyToken=31bf3856ad364e35" name="AzureDiagnostics">           <filter type="" />         </add>       </listeners>     </trace>   </system.diagnostics> Suddenly all the rich tracing info I needed was filling up my storage account.  After a few cycles of trying to attempting to scale, I identified the cert problem, uploaded a correct certificate, and away it went.  I hope this was helpful.

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• career in Mobile sw/Application Development [closed]

  - by pramod

  i m planning to do a course on Wireless & mobile computing.The syllabus are given below.Please check & let me know whether its worth to do.How is the job prospects after that.I m a fresher & from electronic Engg.The modules are- *Wireless and Mobile Computing (WiMC) – Modules* C, C++ Programming and Data Structures 100 Hours C Revision C, C++ programming tools on linux(Vi editor, gdb etc.) OOP concepts Programming constructs Functions Access Specifiers Classes and Objects Overloading Inheritance Polymorphism Templates Data Structures in C++ Arrays, stacks, Queues, Linked Lists( Singly, Doubly, Circular) Trees, Threaded trees, AVL Trees Graphs, Sorting (bubble, Quick, Heap , Merge) System Development Methodology 18 Hours Software life cycle and various life cycle models Project Management Software: A Process Various Phases in s/w Development Risk Analysis and Management Software Quality Assurance Introduction to Coding Standards Software Project Management Testing Strategies and Tactics Project Management and Introduction to Risk Management Java Programming 110 Hours Data Types, Operators and Language Constructs Classes and Objects, Inner Classes and Inheritance Inheritance Interface and Package Exceptions Threads Java.lang Java.util Java.awt Java.io Java.applet Java.swing XML, XSL, DTD Java n/w programming Introduction to servlet Mobile and Wireless Technologies 30 Hours Basics of Wireless Technologies Cellular Communication: Single cell systems, multi-cell systems, frequency reuse, analog cellular systems, digital cellular systems GSM standard: Mobile Station, BTS, BSC, MSC, SMS sever, call processing and protocols CDMA standard: spread spectrum technologies, 2.5G and 3G Systems: HSCSD, GPRS, W-CDMA/UMTS,3GPP and international roaming, Multimedia services CDMA based cellular mobile communication systems Wireless Personal Area Networks: Bluetooth, IEEE 802.11a/b/g standards Mobile Handset Device Interfacing: Data Cables, IrDA, Bluetooth, Touch- Screen Interfacing Wireless Security, Telemetry Java Wireless Programming and Applications Development(J2ME) 100 Hours J2ME Architecture The CLDC and the KVM Tools and Development Process Classification of CLDC Target Devices CLDC Collections API CLDC Streams Model MIDlets MIDlet Lifecycle MIDP Programming MIDP Event Architecture High-Level Event Handling Low-Level Event Handling The CLDC Streams Model The CLDC Networking Package The MIDP Implementation Introduction to WAP, WML Script and XHTML Introduction to Multimedia Messaging Services (MMS) Symbian Programming 60 Hours Symbian OS basics Symbian OS services Symbian OS organization GUI approaches ROM building Debugging Hardware abstraction Base porting Symbian OS reference design porting File systems Overview of Symbian OS Development – DevKits, CustKits and SDKs CodeWarrior Tool Application & UI Development Client Server Framework ECOM STDLIB in Symbian iPhone Programming 80 Hours Introducing iPhone core specifications Understanding iPhone input and output Designing web pages for the iPhone Capturing iPhone events Introducing the webkit CSS transforms transitions and animations Using iUI for web apps Using Canvas for web apps Building web apps with Dashcode Writing Dashcode programs Debugging iPhone web pages SDK programming for web developers An introduction to object-oriented programming Introducing the iPhone OS Using Xcode and Interface builder Programming with the SDK Toolkit OS Concepts & Linux Programming 60 Hours Operating System Concepts What is an OS? Processes Scheduling & Synchronization Memory management Virtual Memory and Paging Linux Architecture Programming in Linux Linux Shell Programming Writing Device Drivers Configuring and Building GNU Cross-tool chain Configuring and Compiling Linux Virtual File System Porting Linux on Target Hardware WinCE.NET and Database Technology 80 Hours Execution Process in .NET Environment Language Interoperability Assemblies Need of C# Operators Namespaces & Assemblies Arrays Preprocessors Delegates and Events Boxing and Unboxing Regular Expression Collections Multithreading Programming Memory Management Exceptions Handling Win Forms Working with database ASP .NET Server Controls and client-side scripts ASP .NET Web Server Controls Validation Controls Principles of database management Need of RDBMS etc Client/Server Computing RDBMS Technologies Codd’s Rules Data Models Normalization Techniques ER Diagrams Data Flow Diagrams Database recovery & backup SQL Android Application 80 Hours Introduction of android Why develop for android Android SDK features Creating android activities Fundamental android UI design Intents, adapters, dialogs Android Technique for saving data Data base in Androids Maps, Geocoding, Location based services Toast, using alarms, Instant messaging Using blue tooth Using Telephony Introducing sensor manager Managing network and wi-fi connection Advanced androids development Linux kernel security Implement AIDL Interface. Project 120 Hours

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• SQLAuthority News – Monthly list of Puzzles and Solutions on SQLAuthority.com

  - by pinaldave

  This month has been very interesting month for SQLAuthority.com we had multiple and various puzzles which everybody participated and lots of interesting conversation which we have shared. Let us start in latest puzzles and continue going down. There are few answers also posted on facebook as well. SQL SERVER – Puzzle Involving NULL – Resolve – Error – Operand data type void type is invalid for sum operator This puzzle involves NULL and throws an error. The challenge is to resolve the error. There are multiple ways to resolve this error. Readers has contributed various methods. Few of them even have supplied the answer why this error is showing up. NULL are very important part of the database and if one of the column has NULL the result can be totally different than the one expected. SQL SERVER – T-SQL Scripts to Find Maximum between Two Numbers I modified script provided by friend to find greatest number between two number. My script has small bug in it. However, lots of readers have suggested better scripts. Madhivanan has written blog post on the subject over here. SQL SERVER – BI Quiz Hint – Performance Tuning Cubes – Hints This quiz is hosted on my friend Jacob‘s site. I have written many hints how one can tune cubes. Now one can take part here and win exciting prizes. SQL SERVER – Solution – Generating Zero Without using Any Numbers in T-SQL Madhivanan has asked very interesting question on his blog about How to Generate Zero without using Any Numbers in T-SQL. He has demonstrated various methods how one can generate Zero. I asked the same question on blog and got many interesting answers which I have shared. SQL SERVER – Solution – Puzzle – Statistics are not Updated but are Created Once I have to accept that this was most difficult puzzle. In this puzzle I have asked even though settings are correct, why statistics of the tables are not getting updated. In this puzzle one is tested with various concepts 1) Indexes, 2) Statistics, 3) database settings etc. There are multiple ways of solving this puzzles. It was interesting as many took interest but only few got it right. SQL SERVER – Question to You – When to use Function and When to use Stored Procedure This is rather straight forward question and not the typical puzzle. The answers from readers are great however, still there is chance of more detailed answers. SQL SERVER – Selecting Domain from Email Address I wrote on selecting domains from email addresses. Madhivanan makes puzzle out of a simple question. He wrote a follow-up post over here. In his post he writes various way how one can find email addresses from list of domains. Well, this is not a puzzle but amazing Guest Post by Feodor Georgiev who has written on subject Job Interviewing the Right Way (and for the Right Reasons). An article which everyone should read. Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: Pinal Dave, PostADay, Readers Contribution, Readers Question, SQL, SQL Authority, SQL Puzzle, SQL Query, SQL Scripts, SQL Server, SQL Tips and Tricks, SQLServer, T SQL, Technology

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• Having fun with Reflection

  - by Nick Harrison

  I was once asked in a technical interview what I could tell them about Reflection.   My response, while a little tongue in cheek was that "I can tell you it is one of my favorite topics to talk about" I did get a laugh out of that and it was a great ice breaker.    Reflection may not be the answer for everything, but it often can be, or maybe even should be.     I have posted in the past about my favorite CopyTo method.   It can come in several forms and is often very useful.   I explain it further and expand on the basic idea here  The basic idea is to allow reflection to loop through the properties of two objects and synchronize the ones that are in common.   I love this approach for data binding and passing data across the layers in an application. Recently I have been working on a project leveraging Data Transfer Objects to pass data through WCF calls.   We won't go into how the architecture got this way, but in essence there is a partial duplicate inheritance hierarchy where there is a related Domain Object for each Data Transfer Object.     The matching objects do not share a common ancestor or common interface but they will have the same properties in common.    By passing the problems with this approach, let's talk about how Reflection and our friendly CopyTo could make the most of this bad situation without having to change too much. One of the problems is keeping the two sets of objects in synch.   For this particular project, the DO has all of the functionality and the DTO is used to simply transfer data back and forth.    Both sets of object have parallel hierarchies with the same properties being defined at the corresponding levels.   So we end with BaseDO,  BaseDTO, GenericDO, GenericDTO, ProcessAreaDO,  ProcessAreaDTO, SpecializedProcessAreaDO, SpecializedProcessAreaDTO, TableDo, TableDto. and so on. Without using Reflection and a CopyTo function, tremendous care and effort must be made to keep the corresponding objects in synch.    New properties can be added at any level in the inheritance and must be kept in synch at all subsequent layers.    For this project we have come up with a clever approach of calling a base GetDo or UpdateDto making sure that the same method at each level of inheritance is called.    Each level is responsible for updating the properties at that level. This is a lot of work and not keeping it in synch can create all manner of problems some of which are very difficult to track down.    The other problem is the type of code that this methods tend to wind up with. You end up with code like this: Transferable dto = new Transferable(); base.GetDto(dto); dto.OfficeCode = GetDtoNullSafe(officeCode); dto.AccessIndicator = GetDtoNullSafe(accessIndicator); dto.CaseStatus = GetDtoNullSafe(caseStatus); dto.CaseStatusReason = GetDtoNullSafe(caseStatusReason); dto.LevelOfService = GetDtoNullSafe(levelOfService); dto.ReferralComments = referralComments; dto.Designation = GetDtoNullSafe(designation); dto.IsGoodCauseClaimed = GetDtoNullSafe(isGoodCauseClaimed); dto.GoodCauseClaimDate = goodCauseClaimDate;       One obvious problem is that this is tedious code.   It is error prone code.    Adding helper functions like GetDtoNullSafe help out immensely, but there is still an easier way. We can bypass the tedious code, by pass the complex inheritance tricks, and reduce all of this to a single method in the base class. TransferObject dto = new TransferObject(); CopyTo (this, dto); return dto; In the case of this one project, such a change eliminated the need for 20% of the total code base and a whole class of unit test cases that made sure that all of the properties were in synch. The impact of such a change also needs to include the on going time savings and the improvements in quality that can arise from them.    Developers who are not worried about keeping the properties in synch across mirrored object hierarchies are freed to worry about more important things like implementing business requirements.

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• jtreg update, March 2012

  - by jjg

  There is a new update for jtreg 4.1, b04, available. The primary changes have been to support faster and more reliable test runs, especially for tests in the jdk/ repository. [ For users inside Oracle, there is preliminary direct support for gathering code coverage data using jcov while running tests, and for generating a coverage report when all the tests have been run. ] -- jtreg can be downloaded from the OpenJDK jtreg page: http://openjdk.java.net/jtreg/. Scratch directories On platforms like Windows, if a test leaves a file open when the test is over, that can cause a problem for downstream tests, because the scratch directory cannot be emptied beforehand. This is addressed in agentvm mode by discarding any agents using that scratch directory and starting new agents using a new empty scratch directory. Successive directives use suffices _1, _2, etc. If you see such directories appearing in the work directory, that is an indication that files were left open in the preceding directory in the series. Locking support Some tests use shared system resources such as fixed port numbers. This causes a problem when running tests concurrently. So, you can now mark a directory such that all the tests within all such directories will be run sequentially, even if you use -concurrency:N on the command line to run the rest of the tests in parallel. This is seen as a short term solution: it is recommended that tests not use shared system resources whenever possible. If you are running multiple instances of jtreg on the same machine at the same time, you can use a new option -lock:file to specify a file to be used for file locking; otherwise, the locking will just be within the JVM used to run jtreg. "autovm mode" By default, if no options to the contrary are given on the command line, tests will be run in othervm mode. Now, a test suite can be marked so that the default execution mode is "agentvm" mode. In conjunction with this, you can now mark a directory such that all the tests within that directory will be run in "othervm" mode. Conceptually, this is equivalent to putting /othervm on every appropriate action on every test in that directory and any subdirectories. This is seen as a short term solution: it is recommended tests be adapted to use agentvm mode, or use "@run main/othervm" explicitly. Info in test result files The user name and jtreg version info are now stored in the properties near the beginning of the .jtr file. Build The makefiles used to build and test jtreg have been reorganized and simplified. jtreg is now using JT Harness version 4.4. Other jtreg provides access to GNOME_DESKTOP_SESSION_ID when set. jtreg ensures that shell tests are given an absolute path for the JDK under test. jtreg now honors the "first sentence rule" for the description given by @summary. jtreg saves the default locale before executing a test in samevm or agentvm mode, and restores it afterwards. Bug fixes jtreg tried to execute a test even if the compilation failed in agentvm mode because of a JVM crash. jtreg did not correctly handle the -compilejdk option. Acknowledgements Thanks to Alan, Amy, Andrey, Brad, Christine, Dima, Max, Mike, Sherman, Steve and others for their help, suggestions, bug reports and for testing this latest version.

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• Software Architecture verses Software Design

  Recently, I was asked what the differences between software architecture and software design are. At a very superficial level both architecture and design seem to mean relatively the same thing. However, if we examine both of these terms further we will find that they are in fact very different due to the level of details they encompass. Software Architecture can be defined as the essence of an application because it deals with high level concepts that do not include any details as to how they will be implemented. To me this gives stakeholders a view of a system or application as if someone was viewing the earth from outer space. At this distance only very basic elements of the earth can be detected like land, weather and water. As the viewer comes closer to earth the details in this view start to become more defined. Details about the earth’s surface will start to actually take form as well as mane made structures will be detected. The process of transitioning a view from outer space to inside our earth’s atmosphere is similar to how an architectural concept is transformed to an architectural design. From this vantage point stakeholders can start to see buildings and other structures as if they were looking out of a small plane window. This distance is still high enough to see a large area of the earth’s surface while still being able to see some details about the surface. This viewing point is very similar to the actual design process of an application in that it takes the very high level architectural concept or concepts and applies concrete design details to form a software design that encompasses the actual implementation details in the form of responsibilities and functions. Examples of these details include: interfaces, components, data, and connections. In review, software architecture deals with high level concepts without regard to any implementation details. Software design on the other hand takes high level concepts and applies concrete details so that software can be implemented. As part of the transition between software architecture to the creation of software design an evaluation on the architecture is recommended. There are several benefits to including this step as part of the transition process. It allows for projects to ensure that they are on the correct path as to meeting the stakeholder’s requirement goals, identifies possible cost savings and can be used to find missing or nonspecific requirements that cause ambiguity in a design. In the book “Evaluating Software Architectures: Methods and Case Studies”, they define key benefits to adding an architectural review process to ensure that an architecture is ready to move on to the design phase. Benefits to evaluating software architecture: Gathers all stakeholders to communicate about the project Goals are clearly defined in regards to the creation or validation of specific requirements Goals are prioritized so that when conflicts occur decisions will be made based on goal priority Defines a clear expectation of the architecture so that all stakeholders have a keen understanding of the project Ensures high quality documentation of the architecture Enables discoveries of architectural reuse  Increases the quality of architecture practices. I can remember a few projects that I worked on that could have really used an architectural review prior to being passed on to developers. This project was to create some new advertising space on the company’s website in order to sell space based on the location and some other criteria. I was one of the developer selected to lead this project and I was given a high level design concept and a long list of ever changing requirements due to the fact that sales department had no clear direction as to what exactly the project was going to do or how they were going to bill the clients once they actually agreed to purchase the Ad space. In my personal opinion IT should have pushed back to have the requirements further articulated instead of forcing programmers to code blindly attempting to build such an ambiguous project.  Unfortunately, we had to suffer with this project for about 4 months when it should have only taken 1.5 to complete due to the constantly changing and unclear requirements. References  Clements, P., Kazman, R., & Klein, M. (2002). Evaluating Software Architectures. Westford, Massachusetts: Courier Westford. 

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• Is this simple XOR encrypted communication absolutely secure?

  - by user3123061

  Say Alice have 4GB USB flash memory and Peter also have 4GB USB flash memory. They once meet and save on both of memories two files named alice_to_peter.key (2GB) and peter_to_alice.key (2GB) which is randomly generated bits. Then they never meet again and communicate electronicaly. Alice also maintains variable called alice_pointer and Peter maintains variable called peter_pointer which is both initially set to zero. Then when Alice needs to send message to Peter they do: encrypted_message_to_peter[n] = message_to_peter[n] XOR alice_to_peter.key[alice_pointer + n] Where n i n-th byte of message. Then alice_pointer is attached at begining of the encrypted message and (alice_pointer + encrypted message) is sent to Peter and then alice_pointer is incremented by length of message (and for maximum security can be used part of key erased) Peter receives encrypted_message, reads alice_pointer stored at beginning of message and do this: message_to_peter[n] = encrypted_message_to_peter[n] XOR alice_to_peter.key[alice_pointer + n] And for maximum security after reading of message also erases used part of key. - EDIT: In fact this step with this simple algorithm (without integrity check and authentication) decreases security, see Paulo Ebermann post below. When Peter needs to send message to Alice they do analogical steps with peter_to_alice.key and with peter_pointer. With this trivial schema they can send for next 50 years each day 2GB / (50 * 365) = cca 115kB of encrypted data in both directions. If they need more data to send, they simple use larger memory for keys for example with today 2TB harddiscs (1TB keys) is possible to exchange next 50years 60MB/day ! (thats practicaly lots of data for example with using compression its more than hour of high quality voice communication) It Seems to me there is no way for attacker to read encrypted message without keys even if they have infinitely fast computer. because even with infinitely fast computer with brute force they get ever possible message that can fit to length of message, but this is astronomical amount of messages and attacker dont know which of them is actual message. I am right? Is this communication schema really absolutely secure? And if its secure, has this communication method its own name? (I mean XOR encryption is well-known, but whats name of this concrete practical application with use large memories at both communication sides for keys? I am humbly expecting that this application has been invented someone before me :-) ) Note: If its absolutely secure then its amazing because with today low cost large memories it is practicaly much cheeper way of secure communication than expensive quantum cryptography and with equivalent security! EDIT: I think it will be more and more practical in future with lower a lower cost of memories. It can solve secure communication forever. Today you have no certainty if someone succesfuly atack to existing ciphers one year later and make its often expensive implementations unsecure. In many cases before comunication exist step where communicating sides meets personaly, thats time to generate large keys. I think its perfect for military communication for example for communication with submarines which can have installed harddrive with large keys and military central can have harddrive for each submarine they have. It can be also practical in everyday life for example for control your bank account because when you create your account you meet with bank etc.

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• Unleash the Power of Cryptography on SPARC T4

  - by B.Koch

  by Rob Ludeman Oracle’s SPARC T4 systems are architected to deliver enhanced value for customer via the inclusion of many integrated features.  One of the best examples of this approach is demonstrated in the on-chip cryptographic support that delivers wire speed encryption capabilities without any impact to application performance.  The Evolution of SPARC Encryption SPARC T-Series systems have a long history of providing this capability, dating back to the release of the first T2000 systems that featured support for on-chip RSA encryption directly in the UltraSPARC T1 processor.  Successive generations have built on this approach by support for additional encryption ciphers that are tightly coupled with the Oracle Solaris 10 and Solaris 11 encryption framework.  While earlier versions of this technology were implemented using co-processors, the SPARC T4 was redesigned with new crypto instructions to eliminate some of the performance overhead associated with the former approach, resulting in much higher performance for encrypted workloads. The Superiority of the SPARC T4 Approach to Crypto As companies continue to engage in more and more e-commerce, the need to provide greater degrees of security for these transactions is more critical than ever before.  Traditional methods of securing data in transit by applications have a number of drawbacks that are addressed by the SPARC T4 cryptographic approach. 1. Performance degradation – cryptography is highly compute intensive and therefore, there is a significant cost when using other architectures without embedded crypto functionality.  This performance penalty impacts the entire system, slowing down performance of web servers (SSL), for example, and potentially bogging down the speed of other business applications.  The SPARC T4 processor enables customers to deliver high levels of security to internal and external customers while not incurring an impact to overall SLAs in their IT environment. 2. Added cost – one of the methods to avoid performance degradation is the addition of add-in cryptographic accelerator cards or external offload engines in other systems.  While these solutions provide a brute force mechanism to avoid the problem of slower system performance, it usually comes at an added cost.  Customers looking to encrypt datacenter traffic without the overhead and expenditure of extra hardware can rely on SPARC T4 systems to deliver the performance necessary without the need to purchase other hardware or add-on cards. 3. Higher complexity – the addition of cryptographic cards or leveraging load balancers to perform encryption tasks results in added complexity from a management standpoint.  With SPARC T4, encryption keys and the framework built into Solaris 10 and 11 means that administrators generally don’t need to spend extra cycles determining how to perform cryptographic functions.  In fact, many of the instructions are built-in and require no user intervention to be utilized.  For example, For OpenSSL on Solaris 11, SPARC T4 crypto is available directly with a new built-in OpenSSL 1.0 engine, called the "t4 engine."  For a deeper technical dive into the new instructions included in SPARC T4, consult Dan Anderson’s blog. Conclusion In summary, SPARC T4 systems offer customers much more value for applications than just increased performance. The integration of key virtualization technologies, embedded encryption, and a true Enterprise Operating System, Oracle Solaris, provides direct business benefits that supersedes the commodity approach to data center computing.   SPARC T4 removes the roadblocks to secure computing by offering integrated crypto accelerators that can save IT organizations in operating cost while delivering higher levels of performance and meeting objectives around compliance. For more on the SPARC T4 family of products, go to here.

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• MEB Support to NetBackup MMS

  - by Hema Sridharan

  In MySQL Enterprise Backup 3.6, new option was introduced to support backup to tapes via SBT interface. SBT stands for System Backup to Tape, an Oracle API that helps to perform backup and restore jobs via media management software such as Oracle's Secure Backup (OSB). There are other storage managers like IBM's Tivoli Storage Manager (TSM) and Symantec's Netbackup (NB) which are also supported by MEB but we don't guarantee that it will function as expected for every release. MEB supports SBT API version 2.0 In this blog, I am primarily going to focus the interface of MEB and Symantec's NB. If we are using tapes for backup, ensure that tape library and tape drives are compatible. Test Setup 1. Install NB 7.5 master and media servers in Linux OS. ( NB 7.1 can also be used but for testing purpose I used NB 7.5)2. Install MEB 3.8 also in Linux OS.3. Install NB admin console in your windows desktop and configure the NB master server from there. Note: Ensure that you have root user permission to install NetBackup. Configuration Steps for MEB and NB Once MEB and NB are installed, Ensure that NB is linked to MEB by specifying the library /usr/openv/netbackup/bin/libobk.so64 in the mysqlbackup command line using --sbt-lib-path. Configure the NB master server from windows console. That is configure the storage units by specifying the Storage unit name, Disk type, Media Server name etc.  Create NetBackup policies that are user selectable. But please make sure that policy type is "Oracle".  Define the clients where MEB will be executed. Some times this will be different host where MEB is run or some times in same Media server where NB and tapes are attached. Now once the installation and configuration steps are performed for MEB and NB, the next part is the actual execution.MEB should be run as single file backup using --backup-image option with prefix sbt:(it is a tag which tells MEB that it should stream the backup image through the SBT interface) which is sent to NB client via SBT interface . The resulting backup image is stored where NB stores the images that it backs up. The following diagram shows how MEB interacts with MMS through SBT interface. Backup The following parameters should also be ready for the execution,    --sbt-lib-path : Path to SBT library specific to NetBackup MMS. SBT lib for NetBackup  is in /usr/openv/netbackup/bin/libobk.so64    --sbt-environment: Environment variables must be defined specific to NetBackup. In our example below, we use     NB_ORA_SERV=myserver.com,    NB_ORA_CLIENT=myserver.com,    NB_ORA_POLICY=NBU-MEB    ORACLE_HOME = /export/home2/tmp/hema/mysql-server/ ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- ./mysqlbackup --port=13000 --protocol=tcp --user=root --backup-image=sbt:bkpsbtNB --sbt-lib-path=/usr/openv/netbackup/bin/libobk.so64 --sbt-environment="NB_ORA_SERV=myserver.com, NB_ORA_CLIENT=myserver.com, NB_ORA_POLICY=NBU-MEB, ORACLE_HOME=/export/home2/tmp/hema/mysql-server/” --backup-dir=/export/home2/tmp/hema/MEB_bkdir/ backup-to-image ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Once backup is completed successfully, this should appear in Activity Monitor in NetBackup Console.For restore,  image contents has to be extracted using image-to-backup-dir command and then apply-log and copy-back steps are applied. ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- ./mysqlbackup --sbt-lib-path=/usr/openv/netbackup/bin/libobk.so64  --backup-dir=/export/home2/tmp/hema/NBMEB/ --backup-image=sbt:bkpsbtNB image-to-backup-dir-----------------------------------------------------------------------------------------------------------------------------------Now apply logs as usual, shutdown the server and perform restore, restart the server and check the data contents. ./mysqlbackup   ---backup-dir=/export/home2/tmp/hema/NBMEB/  apply-log ./mysqlbackup --datadir=/export/home2/tmp/hema/mysql-server/mysql-5.5-meb-repo/mysql-test/var/mysqld.1/data/  --backup-dir=/export/home2/tmp/hema/MEB_bkpdir/ innodb_log_files_in_group=2 --innodb_log_file_size=5M --user=root --port=13000 --protocol=tcp copy-back The NB console should show 'Restore" job as done. If you don't see that there is something wrong with MEB or NetBackup.You can also refer to more detailed steps of MEB and NB integration in whitepaper here

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• Implementing features in an Entity System

  - by Bane

  After asking two questions on Entity Systems (1, 2), and reading some articles on them, I think that I understand them much better than before. But, I still have some uncertainties, and mainly they are about building a Particle Emitter, an Input system, and a Camera. I obviously still have some problems understanding Entity Systems, and they might apply to a whole other range of objects, but I chose these three because they are very different concepts and should cover a pretty big ground, and help me understand Entity Systems and how to handle problems like these myself, as they come along. I am building an engine in Javascript, and I've implemented most of the core features, which include: input handling, flexible animation system, particle emitter, math classes and functions, scene handling, a camera and a render, and a whole bunch of other things that engines usually support. Then, I read Byte56's answer that got me interested into making the engine into an Entity System one. It would still remain an HTML5 game engine with the basic Scene philosophy, but it should support dynamic creation of entities from components. These are some of the definitions from the previous questions, updated: An Entity is an identifier. It doesn't have any data, it's not an object, it's a simple id that represents an index in the Scene's list of all entities (which I actually plan to implement as a component matrix). A Component is a data holder, but with methods that can operate on that data. The best example is a Vector2D, or a "Position" component. It has data: x and y, but also some methods that make operating on the data a bit easier: add(), normalize(), and so on. A System is something that can operate on a set of entities that meet the certain requirements, usually they (the entities) need to have a specified (by the system itself) set of components to be operated upon. The system is the "logic" part, the "algorithm" part, all the functionality supplied by components is purely for easier data management. The problem that I have now is fitting my old engine concept into this new programming paradigm. Lets start with the simplest one, a Camera. The camera has a position property (Vector2D), a rotation property and some methods for centering it around a point. Each frame, it is fed to a renderer, along with a scene, and all the objects are translated according to it's position. Then the scene is rendered. How could I represent this kind of an object in an Entity System? Would the camera be an entity or simply a component? A combination (see my answer)? Another issues that is bothering me is implementing a Particle Emitter. For what exactly I mean by that, you can check out my video of it: http://youtu.be/BObargIMQsE. The problem I have with this is, again, what should be what. I'm pretty sure that particles themselves shouldn't be entities, as I want to support 10k+ of them, and creating that much entities would be a heavy blow on my performance, I believe. Or maybe not? Depends on the implementation, but anyone with experience: please, do answer. The last bit I wan't to talk about, which is also bugging me the most, is how input should be handled. In my current version of the engine, there is a class called Input. It's a handler that subscribes to browser's events, such as keypresses, and mouse position changes, and also it maintains an internal state. Then, the player class has a react() method, which accepts an input object as an argument. The advantage of this is that the input object could be serialized into JSON and then shared over the network, allowing for smooth multiplayer simulations. But how does this translate into an Entity System?

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• Merge sort versus quick sort performance

  - by Giorgio

  I have implemented merge sort and quick sort using C (GCC 4.4.3 on Ubuntu 10.04 running on a 4 GB RAM laptop with an Intel DUO CPU at 2GHz) and I wanted to compare the performance of the two algorithms. The prototypes of the sorting functions are: void merge_sort(const char **lines, int start, int end); void quick_sort(const char **lines, int start, int end); i.e. both take an array of pointers to strings and sort the elements with index i : start <= i <= end. I have produced some files containing random strings with length on average 4.5 characters. The test files range from 100 lines to 10000000 lines. I was a bit surprised by the results because, even though I know that merge sort has complexity O(n log(n)) while quick sort is O(n^2), I have often read that on average quick sort should be as fast as merge sort. However, my results are the following. Up to 10000 strings, both algorithms perform equally well. For 10000 strings, both require about 0.007 seconds. For 100000 strings, merge sort is slightly faster with 0.095 s against 0.121 s. For 1000000 strings merge sort takes 1.287 s against 5.233 s of quick sort. For 5000000 strings merge sort takes 7.582 s against 118.240 s of quick sort. For 10000000 strings merge sort takes 16.305 s against 1202.918 s of quick sort. So my question is: are my results as expected, meaning that quick sort is comparable in speed to merge sort for small inputs but, as the size of the input data grows, the fact that its complexity is quadratic will become evident? Here is a sketch of what I did. In the merge sort implementation, the partitioning consists in calling merge sort recursively, i.e. merge_sort(lines, start, (start + end) / 2); merge_sort(lines, 1 + (start + end) / 2, end); Merging of the two sorted sub-array is performed by reading the data from the array lines and writing it to a global temporary array of pointers (this global array is allocate only once). After each merge the pointers are copied back to the original array. So the strings are stored once but I need twice as much memory for the pointers. For quick sort, the partition function chooses the last element of the array to sort as the pivot and scans the previous elements in one loop. After it has produced a partition of the type start ... {elements <= pivot} ... pivotIndex ... {elements > pivot} ... end it calls itself recursively: quick_sort(lines, start, pivotIndex - 1); quick_sort(lines, pivotIndex + 1, end); Note that this quick sort implementation sorts the array in-place and does not require additional memory, therefore it is more memory efficient than the merge sort implementation. So my question is: is there a better way to implement quick sort that is worthwhile trying out? If I improve the quick sort implementation and perform more tests on different data sets (computing the average of the running times on different data sets) can I expect a better performance of quick sort wrt merge sort? EDIT Thank you for your answers. My implementation is in-place and is based on the pseudo-code I have found on wikipedia in Section In-place version: function partition(array, 'left', 'right', 'pivotIndex') where I choose the last element in the range to be sorted as a pivot, i.e. pivotIndex := right. I have checked the code over and over again and it seems correct to me. In order to rule out the case that I am using the wrong implementation I have uploaded the source code on github (in case you would like to take a look at it). Your answers seem to suggest that I am using the wrong test data. I will look into it and try out different test data sets. I will report as soon as I have some results.

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• Lenovo X220 right click does not work with ubuntu 12.04

  - by fulop

  I am unable to right click with my new X220 Lenovo sub-notebook. I have read several workaround but even not know which one would help me. Can someone help me to find the solution or workaround? dpkg-buildpackage: export CFLAGS from dpkg-buildflags (origin: vendor): -g -O2 -fstack-protector --param=ssp-buffer-size=4 -Wformat -Wformat-security dpkg-buildpackage: export CPPFLAGS from dpkg-buildflags (origin: vendor): -D_FORTIFY_SOURCE=2 dpkg-buildpackage: export CXXFLAGS from dpkg-buildflags (origin: vendor): -g -O2 -fstack-protector --param=ssp-buffer-size=4 -Wformat -Wformat-security dpkg-buildpackage: export FFLAGS from dpkg-buildflags (origin: vendor): -g -O2 dpkg-buildpackage: export LDFLAGS from dpkg-buildflags (origin: vendor): -Wl,-Bsymbolic-functions -Wl,-z,relro dpkg-buildpackage: source package xserver-xorg-input-synaptics dpkg-buildpackage: source version 1.6.2-1ubuntu1~precise2 dpkg-buildpackage: source changed by Timo Aaltonen <[email protected]> dpkg-buildpackage: host architecture amd64 dpkg-source --before-build xserver-xorg-input-synaptics-1.6.2 fakeroot debian/rules clean dh clean --with quilt,autoreconf,xsf --builddirectory=build/ dh_testdir -O--builddirectory=build/ dh_auto_clean -O--builddirectory=build/ dh_quilt_unpatch -O--builddirectory=build/ Removing patch 131_reset-num_active_touches-on-deviceoff.patch Restoring src/synaptics.c Removing patch 130_dont_enable_rightbutton_area.patch Restoring conf/50-synaptics.conf Removing patch 129_disable_three_touch_tap.patch Restoring src/synaptics.c Removing patch 128_disable_three_click_action.patch Restoring src/synaptics.c Removing patch 126_ubuntu_xi22.patch Restoring configure.ac Removing patch 125_option_rec_revert.patch Restoring test/fake-symbols.h Restoring test/fake-symbols.c Removing patch 124_syndaemon_events.patch Restoring tools/syndaemon.c Removing patch 118_quell_error_msg.patch Restoring tools/synclient.c Restoring tools/syndaemon.c Removing patch 115_evdev_only.patch Restoring conf/50-synaptics.conf Removing patch 106_always_enable_vert_edge_scroll.patch Restoring src/synaptics.c Removing patch 104_always_enable_tapping.patch Restoring src/synaptics.c Removing patch 103_enable_cornertapping.patch Restoring src/synaptics.c Removing patch 101_resolution_detect_option.patch Restoring include/synaptics-properties.h Restoring man/synaptics.man Restoring src/synapticsstr.h Restoring src/properties.c Restoring src/synaptics.c Restoring tools/synclient.c Removing patch 02-do-not-use-synaptics-for-keyboards.patch Restoring conf/11-x11-synaptics.fdi No patches applied dh_autoreconf_clean -O--builddirectory=build/ dh_clean -O--builddirectory=build/ dpkg-source -b xserver-xorg-input-synaptics-1.6.2 dpkg-source: warning: no source format specified in debian/source/format, see dpkg-source(1) dpkg-source: info: using source format `1.0' dpkg-source: info: building xserver-xorg-input-synaptics using existing xserver-xorg-input-synaptics_1.6.2.orig.tar.gz dpkg-source: info: building xserver-xorg-input-synaptics in xserver-xorg-input-synaptics_1.6.2-1ubuntu1~precise2.diff.gz dpkg-source: warning: the diff modifies the following upstream files: autogen.sh docs/README.alps docs/tapndrag.dia docs/trouble-shooting.txt dpkg-source: info: use the '3.0 (quilt)' format to have separate and documented changes to upstream files, see dpkg-source(1) dpkg-source: info: building xserver-xorg-input-synaptics in xserver-xorg-input-synaptics_1.6.2-1ubuntu1~precise2.dsc debian/rules build dh build --with quilt,autoreconf,xsf --builddirectory=build/ dh_testdir -O--builddirectory=build/ dh_quilt_patch -O--builddirectory=build/ Applying patch 02-do-not-use-synaptics-for-keyboards.patch patching file conf/11-x11-synaptics.fdi Hunk #1 succeeded at 9 (offset 7 lines). Applying patch 101_resolution_detect_option.patch patching file include/synaptics-properties.h patching file man/synaptics.man patching file src/properties.c Hunk #3 succeeded at 787 (offset 6 lines). patching file src/synaptics.c Hunk #2 succeeded at 1403 (offset 3 lines). Hunk #3 succeeded at 1421 (offset 3 lines). patching file src/synapticsstr.h patching file tools/synclient.c Applying patch 103_enable_cornertapping.patch patching file src/synaptics.c Hunk #1 succeeded at 762 with fuzz 1 (offset 202 lines). Applying patch 104_always_enable_tapping.patch patching file src/synaptics.c Hunk #1 succeeded at 662 with fuzz 2 (offset 6 lines). Applying patch 106_always_enable_vert_edge_scroll.patch patching file src/synaptics.c Hunk #1 succeeded at 673 (offset 174 lines). Applying patch 115_evdev_only.patch patching file conf/50-synaptics.conf Hunk #1 succeeded at 14 with fuzz 2. Applying patch 118_quell_error_msg.patch patching file tools/synclient.c patching file tools/syndaemon.c Applying patch 124_syndaemon_events.patch patching file tools/syndaemon.c Applying patch 125_option_rec_revert.patch patching file test/fake-symbols.c patching file test/fake-symbols.h Applying patch 126_ubuntu_xi22.patch patching file configure.ac Applying patch 128_disable_three_click_action.patch patching file src/synaptics.c Hunk #1 succeeded at 671 (offset 174 lines). Applying patch 129_disable_three_touch_tap.patch patching file src/synaptics.c Hunk #1 succeeded at 665 (offset 32 lines). Applying patch 130_dont_enable_rightbutton_area.patch patching file conf/50-synaptics.conf Applying patch 131_reset-num_active_touches-on-deviceoff.patch patching file src/synaptics.c Applying patch 201-wait.patch patching file src/eventcomm.c Hunk #1 FAILED at 750. Hunk #2 FAILED at 775. Hunk #3 FAILED at 784. 3 out of 3 hunks FAILED -- rejects in file src/eventcomm.c Patch 201-wait.patch does not apply (enforce with -f) dh_quilt_patch: quilt --quiltrc /dev/null push -a || test $? = 2 returned exit code 1 make: *** [build] Error 25 dpkg-buildpackage: error: debian/rules build gave error exit status 2

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• FairWarning Privacy Monitoring Solutions Rely on MySQL to Secure Patient Data

  - by Rebecca Hansen

  FairWarning® solutions have audited well over 120 billion events, each of which was processed and stored in a MySQL database. FairWarning is the world's leading supplier of privacy monitoring solutions for electronic health records, relied on by over 1,200 Hospitals and 5,000 Clinics to keep their patients' data safe. In January 2014, FairWarning was awarded the highest commendation in healthcare IT as the first ever Category Leader for Patient Privacy Monitoring in the "2013 Best in KLAS: Software & Services" report[1]. FairWarning has used MySQL as their solutions’ database from their start in 2005 to worldwide expansion and market leadership. FairWarning recently migrated their solutions from MyISAM to InnoDB and updated from MySQL 5.5 to 5.6. Following are some of benefits they’ve had as a result of those changes and reasons for their continued reliance on MySQL (from FairWarning MySQL Case Study). Scalability to Handle Terabytes of Data FairWarning's customers have a lot of data: On average, FairWarning customers receive over 700,000 events to be processed daily. Over 25% of their customers receive over 30 million events per day, which equates to over 1 billion events and nearly one terabyte (TB) of new data each month. Databases range in size from a few hundred GBs to 10+ TBs for enterprise deployments (data are rolled off after 13 months). Low or Zero Admin = Few DBAs "MySQL has not required a lot of administration. After it's been tuned, configured, and optimized for size on initial setup, we have very low administrative costs. I can scale and add more customers without adding DBAs. This has had a big, positive impact on our business.” - Chris Arnold, FairWarning Vice President of Product Management and Engineering. Performance Schema  As the size of FairWarning's customers has increased, so have their tables and data volumes. MySQL 5.6’ new maintenance and management features have helped FairWarning keep up. In particular, MySQL 5.6 performance schema’s low-level metrics have provided critical insight into how the system is performing and why. Support for Mutli-CPU Threads MySQL 5.6' support for multiple concurrent CPU threads, and FairWarning's custom data loader allow multiple files to load into a single table simultaneously vs. one at a time. As a result, their data load time has been reduced by 500%. MySQL Enterprise Hot Backup Because hospitals and clinics never stop, FairWarning solutions can’t either. FairWarning changed from using mysqldump to MySQL Enterprise Hot Backup, which has reduced downtime, restore time, and storage requirements. For many of their larger customers, restore time has decreased by 80%. MySQL Enterprise Edition and Product Roadmap Provide Complete Solution "MySQL's product roadmap fully addresses our needs. We like the fact that MySQL Enterprise Edition has everything included; there's no need to purchase separate modules."  - Chris Arnold Learn More>> FairWarning MySQL Case Study Why MySQL 5.6 is an Even Better Embedded Database for Your Products presentation Updating Your Products to MySQL 5.6, Best Practices for OEMs on-demand webinar (audio and / or slides + Q&A transcript) MyISAM to InnoDB – Why and How on-demand webinar (same stuff) Top 10 Reasons to Use MySQL as an Embedded Database white paper [1] 2013 Best in KLAS: Software & Services report, January, 2014. © 2014 KLAS Enterprises, LLC. All rights reserved.

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• MySQL Cluster 7.3: On-Demand Webinar and Q&A Available

  - by Mat Keep

  The on-demand webinar for the MySQL Cluster 7.3 Development Release is now available. You can learn more about the design, implementation and getting started with all of the new MySQL Cluster 7.3 features from the comfort and convenience of your own device, including: - Foreign Key constraints in MySQL Cluster - Node.js NoSQL API  - Auto-installation of higher performance distributed, clusters We received some great questions over the course of the webinar, and I wanted to share those for the benefit of a broader audience. Q. What Foreign Key actions are supported: A. The core referential actions defined in the SQL:2003 standard are implemented: CASCADE RESTRICT NO ACTION SET NULL Q. Where are Foreign Keys implemented, ie data nodes or SQL nodes? A. They are implemented in the data nodes, therefore can be enforced for both the SQL and NoSQL APIs Q. Are they compatible with the InnoDB Foreign Key implementation? A. Yes, with the following exceptions: - InnoDB doesn’t support “No Action” constraints, MySQL Cluster does - You can choose to suspend FK constraint enforcement with InnoDB using the FOREIGN_KEY_CHECKS parameter; at the moment, MySQL Cluster ignores that parameter. - You cannot set up FKs between 2 tables where one is stored using MySQL Cluster and the other InnoDB. - You cannot change primary keys through the NDB API which means that the MySQL Server actually has to simulate such operations by deleting and re-adding the row. If the PK in the parent table has a FK constraint on it then this causes non-ideal behaviour. With Restrict or No Action constraints, the change will result in an error. With Cascaded constraints, you’d want the rows in the child table to be updated with the new FK value but, the implicit delete of the row from the parent table would remove the associated rows from the child table and the subsequent implicit insert into the parent wouldn’t reinstate the child rows. For this reason, an attempt to add an ON UPDATE CASCADE where the parent column is a primary key will be rejected. Q. Does adding or dropping Foreign Keys cause downtime due to a schema change? A. Nope, this is an online operation. MySQL Cluster supports a number of on-line schema changes, ie adding and dropping indexes, adding columns, etc. Q. Where can I see an example of node.js with MySQL Cluster? A. Check out the tutorial and download the code from GitHub Q. Can I use the auto-installer to support remote deployments? How about setting up MySQL Cluster 7.2? A. Yes to both! Q. Can I get a demo Check out the tutorial. You can download the code from http://labs.mysql.com/ Go to Select Build drop-down box Q. What is be minimum internet speen required for Geo distributed cluster with synchronous replication? A. if you're splitting you cluster between sites then we recommend a network latency of 20ms or less. Alternatively, use MySQL asynchronous replication where the latency of your WAN doesn't impact the latency of your reads/writes. Q. Where you can one learn more about the PayPal project with MySQL Cluster? A. Take a look at the following - you'll find press coverage, a video and slides from their keynote presentation  So, if you want to learn more, listen to the new MySQL Cluster 7.3 on-demand webinar  MySQL Cluster 7.3 is still in the development phase, so it would be great to get your feedback on these new features, and things you want to see!

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• Page output caching for dynamic web applications

  - by Mike Ellis

  I am currently working on a web application where the user steps (forward or back) through a series of pages with "Next" and "Previous" buttons, entering data until they reach a page with the "Finish" button. Until finished, all data is stored in Session state, then sent to the mainframe database via web services at the end of the process. Some of the pages display data from previous pages in order to collect additional information. These pages can never be cached because they are different for every user. For pages that don't display this dynamic data, they can be cached, but only the first time they load. After that, the data that was previously entered needs to be displayed. This requires Page_Load to fire, which means the page can't be cached at that point. A couple of weeks ago, I knew almost nothing about implementing page caching. Now I still don't know much, but I know a little bit, and here is the solution that I developed with the help of others on my team and a lot of reading and trial-and-error. We have a base page class defined from which all pages inherit. In this class I have defined a method that sets the caching settings programmatically. For pages that can be cached, they call this base page method in their Page_Load event within a if(!IsPostBack) block, which ensures that only the page itself gets cached, not the data on the page. if(!IsPostBack) {     ...     SetCacheSettings();     ... } protected void SetCacheSettings() {     Response.Cache.AddValidationCallback(new HttpCacheValidateHandler(Validate), null);     Response.Cache.SetExpires(DateTime.Now.AddHours(1));     Response.Cache.SetSlidingExpiration(true);     Response.Cache.SetValidUntilExpires(true);     Response.Cache.SetCacheability(HttpCacheability.ServerAndNoCache); } The AddValidationCallback sets up an HttpCacheValidateHandler method called Validate which runs logic when a cached page is requested. The Validate method signature is standard for this method type. public static void Validate(HttpContext context, Object data, ref HttpValidationStatus status) {     string visited = context.Request.QueryString["v"];     if (visited != null && "1".Equals(visited))     {         status = HttpValidationStatus.IgnoreThisRequest; //force a page load     }     else     {         status = HttpValidationStatus.Valid; //load from cache     } } I am using the HttpValidationStatus values IgnoreThisRequest or Valid which forces the Page_Load event method to run or allows the page to load from cache, respectively. Which one is set depends on the value in the querystring. The value in the querystring is set up on each page in the "Next" and "Previous" button click event methods based on whether the page that the button click is taking the user to has any data on it or not. bool hasData = HasPageBeenVisited(url); if (hasData) {     url += VISITED; } Response.Redirect(url); The HasPageBeenVisited method determines whether the destination page has any data on it by checking one of its required data fields. (I won't include it here because it is very system-dependent.) VISITED is a string constant containing "?v=1" and gets appended to the url if the destination page has been visited. The reason this logic is within the "Next" and "Previous" button click event methods is because 1) the Validate method is static which doesn't allow it to access non-static data such as the data fields for a particular page, and 2) at the time at which the Validate method runs, either the data has not yet been deserialized from Session state or is not available (different AppDomain?) because anytime I accessed the Session state information from the Validate method, it was always empty.

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• Is SugarCRM really adequate for custom development (or adequate at all)? [closed]

  - by dukeofgaming

  Have you used SugarCRM for custom development successfully?, if so, have you done it programmatically or through the Module Builder? Were you successful? If not, why? I used SugarCRM for a project about two years ago, I ran into errors from the very installation, having to hack the actual installation file to deploy the software in the server and other erros that I can't recall now. Two years after, I'm picking it up for a project once again. I'm feeling like I should have developed the whole thing from scratch myself. Some examples: I couldn't install it in the server (again). I had to install it locally, then copy the files and database over to the server and manually edit the config file. Constantly getting deployment errors from the module builder. One reason is SugarCRM keeps creating a record in the upgrade_history table for a file that does not exist, I keep deleting such record and it keeps coming back corrupt. I get other deployment errors, but have not figured them out. then I have to rollback all files and database to try again. I deleted a custom module with relationships, the relationships stayed in the other modules and cannot be deleted anymore, PHP warnings all over the place. Quick create for custom modules does not appear, hack needed. Its whole cache directory is a joke, permanent data/files are stored there. The module builder interface disappears required fields. Edit the wrong thing, module builder won't deploy again, then pray Quick Repair and/or Rebuild Relationships do the trick. My impression of SugarCRM now is that, regardless of its pretty exterior and apparent functionality, it is a very low quality piece of software. This even scared me more: http://amplicate.com/hate/sugarcrm; a quote: I wis this info had been available when I tried to implement it 2 years ago... I searched high and low and the only info I found was positive. Yes, it's a piece of crap. The community edition was full of bugs... nothing worked. Essentially I got fired for implementing it. I'm glad though, because now I work for myself, am much happier and make more money... so, I should really thank SugarCRM for sucking so much I guess! I figured that perhaps some of you have had similar experiences, and have either sticked with SugarCRM or moved on to another solution. I'm very interested in knowing what your resolutions were -or your current situations are- to make up my own mind, since the project I'm working on is long term and I'm feeling SugarCRM will be more an obstacle than an aid. After further failed attempts to continue using this software I continued to stumble upon dead-ends when using the module editor, I could only recover from this errors by using version control. We are now moving on to a custom implementation using Symfony; perhaps if we were using it with its out-of-the-box modules we would have sticked with it.

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• Speeding up procedural texture generation

  - by FalconNL

  Recently I've begun working on a game that takes place in a procedurally generated solar system. After a bit of a learning curve (having neither worked with Scala, OpenGL 2 ES or Libgdx before), I have a basic tech demo going where you spin around a single procedurally textured planet: The problem I'm running into is the performance of the texture generation. A quick overview of what I'm doing: a planet is a cube that has been deformed to a sphere. To each side, a n x n (e.g. 256 x 256) texture is applied, which are bundled in one 8n x n texture that is sent to the fragment shader. The last two spaces are not used, they're only there to make sure the width is a power of 2. The texture is currently generated on the CPU, using the updated 2012 version of the simplex noise algorithm linked to in the paper 'Simplex noise demystified'. The scene I'm using to test the algorithm contains two spheres: the planet and the background. Both use a greyscale texture consisting of six octaves of 3D simplex noise, so for example if we choose 128x128 as the texture size there are 128 x 128 x 6 x 2 x 6 = about 1.2 million calls to the noise function. The closest you will get to the planet is about what's shown in the screenshot and since the game's target resolution is 1280x720 that means I'd prefer to use 512x512 textures. Combine that with the fact the actual textures will of course be more complicated than basic noise (There will be a day and night texture, blended in the fragment shader based on sunlight, and a specular mask. I need noise for continents, terrain color variation, clouds, city lights, etc.) and we're looking at something like 512 x 512 x 6 x 3 x 15 = 70 million noise calls for the planet alone. In the final game, there will be activities when traveling between planets, so a wait of 5 or 10 seconds, possibly 20, would be acceptable since I can calculate the texture in the background while traveling, though obviously the faster the better. Getting back to our test scene, performance on my PC isn't too terrible, though still too slow considering the final result is going to be about 60 times worse: 128x128 : 0.1s 256x256 : 0.4s 512x512 : 1.7s This is after I moved all performance-critical code to Java, since trying to do so in Scala was a lot worse. Running this on my phone (a Samsung Galaxy S3), however, produces a more problematic result: 128x128 : 2s 256x256 : 7s 512x512 : 29s Already far too long, and that's not even factoring in the fact that it'll be minutes instead of seconds in the final version. Clearly something needs to be done. Personally, I see a few potential avenues, though I'm not particularly keen on any of them yet: Don't precalculate the textures, but let the fragment shader calculate everything. Probably not feasible, because at one point I had the background as a fullscreen quad with a pixel shader and I got about 1 fps on my phone. Use the GPU to render the texture once, store it and use the stored texture from then on. Upside: might be faster than doing it on the CPU since the GPU is supposed to be faster at floating point calculations. Downside: effects that cannot (easily) be expressed as functions of simplex noise (e.g. gas planet vortices, moon craters, etc.) are a lot more difficult to code in GLSL than in Scala/Java. Calculate a large amount of noise textures and ship them with the application. I'd like to avoid this if at all possible. Lower the resolution. Buys me a 4x performance gain, which isn't really enough plus I lose a lot of quality. Find a faster noise algorithm. If anyone has one I'm all ears, but simplex is already supposed to be faster than perlin. Adopt a pixel art style, allowing for lower resolution textures and fewer noise octaves. While I originally envisioned the game in this style, I've come to prefer the realistic approach. I'm doing something wrong and the performance should already be one or two orders of magnitude better. If this is the case, please let me know. If anyone has any suggestions, tips, workarounds, or other comments regarding this problem I'd love to hear them.

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• Monitor and Control Memory Usage in Google Chrome

  - by Asian Angel

  Do you want to know just how much memory Google Chrome and any installed extensions are using at a given moment? With just a few clicks you can see just what is going on under the hood of your browser. How Much Memory are the Extensions Using? Here is our test browser with a new tab and the Extensions Page open, five enabled extensions, and one disabled at the moment. You can access Chrome’s Task Manager using the Page Menu, going to Developer, and selecting Task manager… Or by right clicking on the Tab Bar and selecting Task manager. There is also a keyboard shortcut (Shift + Esc) available for the “keyboard ninjas”. Sitting idle as shown above here are the stats for our test browser. All of the extensions are sitting there eating memory even though some of them are not available/active for use on our new tab and Extensions Page. Not so good… If the default layout is not to your liking then you can easily modify the information that is available by right clicking and adding/removing extra columns as desired. For our example we added Shared Memory & Private Memory. Using the about:memory Page to View Memory Usage Want even more detail? Type about:memory into the Address Bar and press Enter. Note: You can also access this page by clicking on the Stats for nerds Link in the lower left corner of the Task Manager Window. Focusing on the four distinct areas you can see the exact version of Chrome that is currently installed on your system… View the Memory & Virtual Memory statistics for Chrome… Note: If you have other browsers running at the same time you can view statistics for them here too. See a list of the Processes currently running… And the Memory & Virtual Memory statistics for those processes. The Difference with the Extensions Disabled Just for fun we decided to disable all of the extension in our test browser… The Task Manager Window is looking rather empty now but the memory consumption has definitely seen an improvement. Comparing Memory Usage for Two Extensions with Similar Functions For our next step we decided to compare the memory usage for two extensions with similar functionality. This can be helpful if you are wanting to keep memory consumption trimmed down as much as possible when deciding between similar extensions. First up was Speed Dial”(see our review here). The stats for Speed Dial…quite a change from what was shown above (~3,000 – 6,000 K). Next up was Incredible StartPage (see our review here). Surprisingly both were nearly identical in the amount of memory being used. Purging Memory Perhaps you like the idea of being able to “purge” some of that excess memory consumption. With a simple command switch modification to Chrome’s shortcut(s) you can add a Purge Memory Button to the Task Manager Window as shown below.  Notice the amount of memory being consumed at the moment… Note: The tutorial for adding the command switch can be found here. One quick click and there is a noticeable drop in memory consumption. Conclusion We hope that our examples here will prove useful to you in managing the memory consumption in your own Google Chrome installation. If you have a computer with limited resources every little bit definitely helps out. Similar Articles Productive Geek Tips Stupid Geek Tricks: Compare Your Browser’s Memory Usage with Google ChromeMonitor CPU, Memory, and Disk IO In Windows 7 with Taskbar MetersFix for Firefox memory leak on WindowsHow to Purge Memory in Google ChromeHow to Make Google Chrome Your Default Browser TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips Acronis Online Backup DVDFab 6 Revo Uninstaller Pro Registry Mechanic 9 for Windows iFixit Offers Gadget Repair Manuals Online Vista style sidebar for Windows 7 Create Nice Charts With These Web Based Tools Track Daily Goals With 42Goals Video Toolbox is a Superb Online Video Editor Fun with 47 charts and graphs

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• WebGrid Helper and Complex Types

  - by imran_ku07

      Introduction:           WebGrid helper makes it very easy to show tabular data. It was originally designed for ASP.NET Web Pages(WebMatrix) to display, edit, page and sort tabular data but you can also use this helper in ASP.NET Web Forms and ASP.NET MVC. When using this helper, sometimes you may run into a problem if you use complex types in this helper. In this article, I will show you how you can use complex types in WebGrid helper.       Description:             Let's say you need to show the employee data and you have the following classes,   public class Employee { public string Name { get; set; } public Address Address { get; set; } public List<string> ContactNumbers { get; set; } } public class Address { public string City { get; set; } }               The Employee class contain a Name, an Address and list of ContactNumbers. You may think that you can easily show City in WebGrid using Address.City, but no. The WebGrid helper will throw an exception at runtime if any Address property is null in the Employee list. Also, you cannot directly show ContactNumbers property. The easiest way to show these properties is to add some additional properties,   public Address NotNullableAddress { get { return Address ?? new Address(); } } public string Contacts { get { return string.Join("; ",ContactNumbers); } }               Now you can easily use these properties in WebGrid. Here is the complete code of this example,  @functions{ public class Employee { public Employee(){ ContactNumbers = new List<string>(); } public string Name { get; set; } public Address Address { get; set; } public List<string> ContactNumbers { get; set; } public Address NotNullableAddress { get { return Address ?? new Address(); } } public string Contacts { get { return string.Join("; ",ContactNumbers); } } } public class Address { public string City { get; set; } } } @{ var myClasses = new List<Employee>{ new Employee { Name="A" , Address = new Address{ City="AA" }, ContactNumbers = new List<string>{"021-216452","9231425651"}}, new Employee { Name="C" , Address = new Address{ City="CC" }}, new Employee { Name="D" , ContactNumbers = new List<string>{"045-14512125","21531212121"}} }; var grid = new WebGrid(source: myClasses); } @grid.GetHtml(columns: grid.Columns( grid.Column("NotNullableAddress.City", header: "City"), grid.Column("Name"), grid.Column("Contacts")))                    Summary:           You can use WebGrid helper to show tabular data in ASP.NET MVC, ASP.NET Web Forms and  ASP.NET Web Pages. Using this helper, you can also show complex types in the grid. In this article, I showed you how you use complex types with WebGrid helper. Hopefully you will enjoy this article too.  

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