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• Docker vs ESXi for Startup Projects - Deploying Code for Dev Testing

  - by JasonG

  Why hello there little programmer dude! I have a question for you and all of your experience and knowledge. I have an ESXi whitebox that I built which is an 8 dude that sits in the corner. I made a mistake recently and took the key that had ESXi, formatted it and used it for something else. No big deal because the last project I worked on had stalled out. I'm about to pick up another project and now I need to spin up a whole bunch of stuff for CI, qa + db, ticket tracker, wikis etc etc. I've been hearing a lot about Docker recently and as this is just a consumer grade machine, I'm wondering if it may make more sense for me to use Docker on OpenOS and then put everything there - bamboo or hudson, jira, confluence, postgress for the tools to use, then a qa env. I can't really seem to find any documents that directly compare traditional VM infrastructure vs docker solutions and I'm wondering if it is fair to compare. Is there any reason why CoreOS w/ containers would be a strictly worse solution? Or do you have any insight into why I may want to stick with ESXi? I've looked on multiple occasions and can't find a good reason not to. I'm not going to run a production env on the server so I don't need to have HA if updating security or OS for example where esxi would allow me to restart one vm at a time. I can just shut the thing down and bring it back up if I need a reboot no problem. So what's up with this container stuff? Is it a fair replacement for ESXi? I'm guessing the atlassian products would run much better and my ram would go a lot farther using docker. Probably the CPU would run much cooler too and my expensive HDD space would be better utilized.

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• Creating a backup - Rsync - Connection refused (111)

  - by pablofiumara

  I am trying to create a backup of my website for free. I just want to have a backup of my website, including not only all files and the configuration but also the databases. I mean, a full backup. If it can be done automatically, it would be better. I feel there are better ways than using the cpanel to achieve that (actually, I believe sometimes web hosters does not have any cpanel). I read the following on how to do it: Automatically mirror the entire contents and configuration of your main server to a secondary backup server on a completely separate network in a different data centre. Use RSync, FXP, cPanel voodoo, or whatever method you wish to automate syncing. That is why I installed Rsync Daemon which is an alternative to SSH for remote backups. I configured it but the test went wrong. The terminal is showing me this: pablofiumara@pablofiumara-Lenovo-G470:~$ sudo rsync [email protected]::share [sudo] password for pablofiumara: rsync: failed to connect to pablofiumara.com (50.87.147.75): Connection refused (111) rsync error: error in socket IO (code 10) at clientserver.c(122) [Receiver=3.0.9] pablofiumara@pablofiumara-Lenovo-G470:~$ sudo rsync [email protected]::share failed to connect to 50.87.147.7 (50.87.147.7): Connection refused (111) rsync error: error in socket IO (code 10) at clientserver.c(122) [Receiver=3.0.9] What should I do? Is there a better or easier way to achieve what I wish (I mentioned this in the first paragraph)?

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• How do you make people accept code review?

  - by user7197

  All programmers have their style of programming. But some of the styles are let’s say... let’s not say. So you have code review to try to impose certain rules for good design and good programming techniques. But most of the programmers don’t like code review. They don’t like other people criticizing their work. Who do they think they are to consider themselves better than me and tell me that this is bad design, this could be done in another way. It works right? What is the problem? This is something they might say (or think but not say which is just as bad if not worse). So how do you make people accept code review without starting a war? How can you convince them this is a good thing; that will only improve their programming skills and avoid a lot of work later to fix and patch a zillion times a thing that hey... "it works"? People will tell you how to make code review (peer-programming, formal inspections etc) what to look for in a code review, studies have been made to show the number of defects that can be discovered before the software hits production etc. But how do you convince programmers to accept a code review?

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• Update to SQL Server Configuration Scripting Utility

  - by Bill Graziano

  Last spring I released a utility to script SQL Server configuration information on CodePlex.  I’ve been making small changes in this application as my needs have changed.  The application is a .NET 2.0 console application.  This utility serves two needs for me.  First it helps with disaster recovery.  All server level objects (logins, jobs, linked servers, audits) are scripted to a single file per object type.  This enables the scripts to be easily run against a DR server.  If these are checked into source control you can view the history of the script and find out what changed and when. The second goal is to capture what changed inside a database.  Objects inside a database (tables, stored procedures, views, etc.) are each scripted to their own file.  This makes it easier to track the changes to an object over time.  This does include permissions and role membership so you can capture security changes.  My assumption is that a database backup is the primary method of disaster recovery for databases so this utility is designed to capture changes to objects.  You can find the full list of changes from the original on the Downloads page on CodePlex.

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• JEOS

  - by john.graves(at)oracle.com

  JEOS stands for Just Enough Operating System.  It is  great environment for building virtual machines without all the clutter of a windowing system, games, office products, etc.  It is from Ubuntu and you install it using the Ubuntu server install, but rather than picking a standard install, press F4 and choose “Install a minimal system.” Note: The “Install a minimal virtual machine” is specific to VMWare and I plan to use VirtualBox. Be sure to include Open SSH in the install so that it installs sshd. *** Also, if you plan to install XE, you’ll need to modify the partitions to have a larger swap space (at least 1.5 G). *** Once the install is done, I find it useful to install a few other items. Update Ubuntu apt-get update Install some other tools apt-get openjdk-6-jre Yes, java will be included in any of the WebLogic installs, but I need this one if I want to do remote display (for config wizards, etc). apt-get gcc Some apps require to rebuild the kernel modules, so you’ll need a basic compiler. Install guest additions (Choose the VirtualBox Devices->Install Guest Additions…” option.  This sets up a /dev/cdrom or /dev/cdrom1.  You’ll need to manually mount this temporarily: sudo mount /dev/cdrom /mnt Then run the linux .bin file. Update nofile limits.  Most java apps fail with the standard ubuntu settings: edit /etc/security/limits.conf and add these lines at the end: *     soft nofile 65535 *     hard nofile 65535 root  soft nofile 65535 root  hard nofile 65535 These numbers are very high and I wouldn’t do this on a production system, but for this environment it is fin. To get rid of the annoying piix error on boot, add the following line to the /etc/modprobe.d/blacklist.conf file blacklist i2c_piix4

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• New features in SQL Prompt 6.4

  - by Tom Crossman

  We’re pleased to announce a new beta version of SQL Prompt. We’ve been trying out a few new core technologies, and used them to add features and bug fixes suggested by users on the SQL Prompt forum and suggestions forum. You can download the SQL Prompt 6.4 beta here (zip file). Let us know what you think! New features Execute current statement In a query window, you can now execute the SQL statement under your cursor by pressing Shift + F5. For example, if you have a query containing two statements and your cursor is placed on the second statement: When you press Shift + F5, only the second statement is executed:   Insert semicolons You can now use SQL Prompt to automatically insert missing semicolons after each statement in a query. To insert semicolons, go to the SQL Prompt menu and click Insert Semicolons. Alternatively, hold Ctrl and press B then C. BEGIN…END block highlighting When you place your cursor over a BEGIN or END keyword, SQL Prompt now automatically highlights the matching keyword: Rename variables and aliases You can now use SQL Prompt to rename all occurrences of a variable or alias in a query. To rename a variable or alias, place your cursor over an instance of the variable or alias you want to rename and press F2: Improved loading dialog box The database loading dialog box now shows actual progress, and you can cancel loading databases:   Single suggestion improvement SQL Prompt no longer suggests keywords if the keyword has been typed and no other suggestions exist. Performance improvement SQL Prompt now has less impact on Management Studio start up time. What do you think? We want to hear your feedback about the beta. If you have any suggestions, or bugs to report, tell us on the SQL Prompt forum or our suggestions forum.

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• invitation: Oracle Endeca Information Discovery Bootcamp

  - by mseika

  The Oracle Endeca Information Discovery (OEID) Boot Camp is designed to give partners an understanding of OEID’s features, and how it complements the existing Oracle Business Intelligence suite. Participants will learn how to develop & implement solutions using a Data Discovery method. Training is in EnglishWhat will be covered?The Oracle Endeca Information Discovery (OEID) Boot Camp is a three-day class with a combination of lecture and hands-on exercises, tailored to make participants aware of the Oracle Endeca Information Discovery platform, and to gain valuable skills for the implementation of projects.The course will follow a combination of lectures and hands-on lab sessions, to allow participants to apply the knowledge they have gained by extracting from sample data sources, and creating an end-user application that will be used to answer several business questions. What You Will Learn Architecture: OEID Components, use of graphs, overview of clustering OEID Installation: Architecture planning, infrastructure requirements, installation process, production hints & tips OEID Administration: Data store management, administrative operations, portal configuration, data sources, system monitoring Indexing: Integration Suite, Data source analysis, Graph (ETL) creation, record design techniques Portlets: Studio portlets, custom portlet development, querying functions Reporting: Studio applications & best practices, visualizations, EQL PrerequisitesYou must bring a laptop with you for the Hands-on labs ENVIRONMENT – LAPTOP REQUIREMENTS For the OEID boot camp, participants will perform the hands-on lab exercises using a virtual machine image. These virtual machines will be provided to participants within a cloud environment, requiring participants to bring a laptop to the Boot Camp that can access a Windows server utilizing Microsoft RDP from their laptop. Participants will not need to install any software onto their laptops, but must ensure that they have the proper software installed for their OS, to connect through RDP to a server. HARDWARE • CPU: Dual-core, x64, 1.8Ghz or higher • RAM: 2GB SOFTWARE • Microsoft Remote Desktop Client • Internet Explorer 7, Firefox, or Google Chrome This boot camp is intended for prospective implementers of Oracle Endeca Information Discovery (OEID), or those in a presales role looking to gain insight into the technical benefits of this new package. Attendees should have experience and familiarity with the basic concepts of business intelligence. Where and When ? Monday, October 15th until wednesday, October 17th included 9:00 - 18:00 Oracle France 15, boulevard Charles de Gaulle 92715 Colombes Access Register Here Limited number of seats !

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• Why is my query soooooo slow?

  - by geekrutherford

  A stored procedure used in our production environment recently became so slow it cause the calling web service to begin timing out. When running the stored procedure in Query Analyzer it took nearly 3 minutes to complete.   The stored procedure itself does little more than create a small bit of dynamic SQL which calls a view with a where clause at the end.   At first the thought was that the query used within the view needed to be optimized. The query is quite long and therefore easy to jump to this conclusion.   Fortunately, after bringing the issue to the attention of a coworker they asked "is there a where clause, and if so, is there an index on the column(s) in it?" I had no idea and quickly said as much. A quick check on the table/column utilized in the where clause indicated indeed there was no index.   Before adding the index, and after admitting I am no SQL wiz, I checked the internet for info on the difference between clustered and non-clustered indexes. I found the following site quite helpful OdeToCode. After adding the non-clustered index on the column, the query that used to take nearly 3 minutes now takes 10 seconds! Ah, if only I'd thought to do this ahead of time!

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• A Quarter Century of SPARC

  - by kemer

  You might have missed an interesting milestone: the 25th anniversary of SPARC. Twenty-five years! Almost 40% of my life: humbling, maybe a little scary. When I joined Sun Microsystems in 1988, SPARC was just starting to shake things up. The next year we introduced the SPARCstation 1, which had basically triple the performance of our Motrolla-based Sun–3 systems. Not too long after that, our competition began a campaign of “SPARC is dead.” We really distressed them with our success, in spite of our small size. “It won’t last.” “It can’t last!” So they told themselves. For a stroll down memory lane take a look at this page. I remember the sales meeting we had in Atlanta to internally announce the SPARCstation 1. Sun hadn’t really hit the big times, yet. Our much bigger competitors viewed us as an ill-mannered pest, certain of our demise. And, why wouldn’t they be certain: other startups more our size, such as Apollo (remember them?), Silicon Graphics (they fought the good fight!), and the incredibly cool Symbolics are memories. Wait! There was also a BIG company, DEC, who scoffed at us: they are history, too. In fact, we really upset them with what was supposed to be an internal-only video production that was a take-off on Bruce Lee movies, in which we battled the evil Doctor DEC – complete with computer mice (or is that “mouses”?) wielded like nun chucks with the new SPARCstation 1 somehow in the middle of everything. The memory is vivid, but the details hazy. After all, that was almost a quarter century ago. So, here’s to Oracle’s SPARC: still going strong after all these years. – Kemer

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• Scripting language for filling out web form

  - by ityler22

  I have a job as an intern at a technology company, I was given the unfortunate job of performing some data entry into our web management system. The information entered into the web form is stored in a MySQL DB. Upon receiving the data I realized I would have to submit this online form about 1000 different times all consisting of about 10 different text fields / check boxes per form. (So in other words, would be completely mind numbing and be a ridiculous waste of time and resources, or so I thought...) Having used databases a good bit prior to this, my immediate reaction was to just write a short MySQL script to bulk import all of the data, especially since it was already presented to me in an excel spreadsheet ready to go. Thought it may have been some sort of a test since it seemed too obvious. I wrote the script which consisted of about 10 lines of code but was then informed I couldn't be trusted with MySQL Admin privileges to run said script. So my next thought would be to write a script to just enter the information through the web form (Which will take ten times longer but it's what I have to) Being unfamiliar with scripting of this nature (seems like I would need something similar to a bot, but the good kind) I was unsure of how to proceed to do this. Is there a preferred language to use to enter the data i have into the web form I do have access to? I'm not particularly looking for this to be done for me by any means just a nice point in the right direction as far as what scripting language to use and how to pair that with the data I have that needs to be entered. Thanks for the help/ valuable input! EDIT: Is there a way to perform this using perl without having access to place any files on the server? Would I be able to run some Javascript loops to pull the data out of .csv or just a .txt format with line delimiters and insert it into the web form?

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• My new favourite traceflag

  - by Dave Ballantyne

  As we are all aware, there are a number of traceflags.  Some documented, some semi-documented and some completely undocumented.  Here is one that is undocumented that Paul White(b|t) mentioned almost as an aside in one of his excellent blog posts. Much has been written about residual predicates and how a predicate can be pushed into a seek/scan operation.  This is a good thing to happen,  it does save a lot of processing from having to be done.  For the uninitiated though: If we have a simple SELECT statement such as : the process that SQL Server goes through to resolve this is : The index IX_Person_LastName_FirstName_MiddleName is navigated to find the first “Smith” For each “Smith” the middle name is checked for being a null. Two operations!, and the execution plan doesnt fully represent all the work that is being undertaken. As you can see there is only a single seek operation, the work undertaken to resolve the condition “MiddleName is not null” has been pushed into it.  This can be seen in the properties. “Seek predicate” is how the index has been navigated, and “Predicate” is the condition run over every row,  a scan inside a seek!. So the question is:  How many rows have been resolved by the seek and how many by the scan ?  How many rows did the filter remove ? Wouldn’t it be nice if this operation could be split ?  That exactly what traceflag 9130 does. Executing the query: That changes the plan rather dramatically, and should be changing how we think about the index seek itself.  The Filter operator has been added and, unsurprisingly, the condition in this is “MiddleName is not null” So it is now evident that the seek operation found 103 Smiths and 60 of those Smiths had a non-null MiddleName. This traceflag has no place on a production system,  dont even think about it

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• Can a candidate be judged by asking to write a complex program on "paper"?

  - by iammilind

  Sometime back in an interview, I was asked to write following program: In a keypad of a mobile phone, there is a mapping between number and characters. e.g. 0 & 1 corresponds to nothing; 2 corresponds to 'a','b','c'; 3 corresponds to 'd','e','f'; ...; 9 corresponds to 'w','x','y','z'. User should input any number (e.g. 23, 389423, 927348923747293) and I should store all the combinations of these character mapping into some data structure. For example, if user enters "23" then possible character combinations are: ad, ae, af, bd, be, bf, cd, ce, cf or if user enters, "4676972" then it can be, gmpmwpa, gmpmwpb, ..., hnroxrc, ..., iosozrc Interviewer told that people have written code for this within 20-30 mins!! Also he insisted I have to write on paper. If I am writing a code then my tendency is as of I am writing production code, even though it may not be expected from me. So, I always try to think all the aspects like, optimization, readability, maintainability, extensible and so on. Considering all these, I felt that I should be writing on PC and it needs decent 2 hours. Finally after 25 mins, I was able to come up with just the concept and some shattered pieces of code (not to mention of my rejection). My question is not the answer for the above program. I want to know that is this a right way to judge the caliber of a person ? Am I wrong / too slow in the estimates ? Am I too idealistic ?

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• How bad would be to focus on iOS/Android development for an indie developer?

  - by kender

  After some time developing games for others I'm thinking of moving towards my own productions. My background is 10+ years of software development, with last 2 years spent on the iOS development (Objective-C and CoronaSDK). With my current experience in Corona I can quickly develop for iOS and Android systems. And this is something that I'm probably gonna do with several of the game ideas I have, at least for the prototype part. But - I'm wondering if it's not a bad idea to focus on those 2 systems only. After all there are other mobile platforms, there are PCs, Macs and Linux boxes... All of them having gamers using them. I was wondering if it wasn't a good idea to try some other SDK, giving me more flexibility when it comes to platform-independance. There's Unity3D (I think I can develop a 2D game in it though), there's MoAI from what I checked. I see a few options, not sure which one is best as I have little experience in this field (publishing own games): Stick with CoronaSDK for the whole time, release for iOS and Android platforms, screw other mobile devices and PCs, Use Corona for prototyping, then when the idea goes more into the "production" phase rewrite it in MoAI or Unity3D for more platforms support, Start with one of those 2 SDKs right now (which means the prototype phase will be delayed a bit, but after that I can jump right into real coding). Any clues here, what to do?

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• How to deal with a valuable person going in all directions?

  - by JVerstry

  I am working with someone producing user content to be included in a software application. He is not a coder, but rather an expert in his field, sharing the knowledge. His contribution, taken piece by piece is great, but he goes in all directions and has issues producing work sequentially. He works on 25 pieces of content at the same time, and as soon as he reads something 'interesting', he wants to rewrite some of his stuff to improve the quality of it. He does not converge naturally. He collects tons of informations, produces some valuable stuff, but in a completely unstructured way. We addressed this issue with him some time ago and in order to try to solve it, we created a document with the 100 items he had to fill. Problem is, it does not seem to work very well. How to deal with those people and collect information? I was thinking about a new technique: ask him to send his bits, out of order, little by little, as soon as they are ready, and keep a list of what remains to be done, and show him that list to give him direction. This situation is stressing the hell out of me. If his production was not good, I would not be trying so hard to make this work. If you have experience to share, it is welcome.

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• Today's Links (6/27/2011)

  - by Bob Rhubart

  2011 Entrepreneurs of the Year, Northern California Region Drake Martinet reports on the new batch of entrepreneurs joining the ranks of Oracle CEO Larry Ellison, Yahoo CEO Carol Bartz and eBay co-founder Pierre Omidyar as the Norther California Region winners of Ernst & Young's Entrepreneurs of the Year awards. Technical Article: Caching Strategies for Oracle Service Bus 11g William Markito Oliveira illustrates how the right caching strategy can make a big difference in application performance. Kscope 11 - Day 1 and 2 Oracle ACE Director Markus Eisele checks in from Long Beach. Kaleidoscope 2011: Sunday’s Symposium And so does Oracle ACE Director Marco Gralike. Yet another GlassFish 3.1.1 promoted build | The Aquarium "This version was carefully designed to be highly compatible with the previous 3.x versions," says Alexis, "thus leaving you with little reasons not to upgrade as soon as it comes out this summer." Using NoSQL database in your Java EE 6 Applications on GlassFish - MongoDB for now! "The NoSQL databases are not intended to be a replacement for the mainstream RDBMS," says Arun Gupta. I have a performance problem | Alan Hargreaves Good (and entertaining) advice from an Australian Solaris and Network Domain TSC* Principal Field Technologist.

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• Having a Proactive Patch Plan is the way to Go!

  - by user793553

  BUILDING A SUCCESSFUL PATCHING STRATEGY Make Patching Easy! Having a Patching Strategy for your E-Business Suite system is a great way to manage your system downtime, identify the proper resources needed to perform the necessary task and familiarizing yourself with the Patching Tools in EBS. Having a Proactive Patch Plan is the way to Go! Proactive Patching is a preventive measure allowing you to have a complete patching strategy when applying patches periodically. Oracle provides several tools to help you get started to set the foundation for a solid and proactive patching strategy in Note 313.1 - "Patching & Maintenance Advisor: E-Business Suite 11i and R12". It details all the steps and tooling available for the patching strategy along with the benefits. Among other things it covers the following: How to plan ahead for system downtime Patching Tools in E-Business Suite (Autopatch, OUI, OPatch) How to Identify Patches (RUPs, EBS Family Packs, Critical Patch Updates, etc) How to properly test your patching plan and move to Production Make sure you visit the New E-Business Patching Community! We encourage you to access the "E-Business Patching Community" prior to applying an E-Business Suite patch. Doing so will allow you to explore perspectives shared by industry peers, get real-world experiences with the patch, and benefit from known solutions and lessons learned. Additionally, Oracle Support engineers monitor discussion topics to help provide guidance and solutions for your E-Business Suite patching needs. This is a valuable opportunity to "Get Proactive" with the patching and maintenance of your E-Business Suite environment. Start now, and find fast, proactive resolutions before you begin. Related Articles: What's the Best Way to Patch an E-Business Suite Environment? Patch Wizard Utility

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• Notification framework for object lifecycle

  - by rlandster

  I am looking for an application, framework, or library that would help us with "object life-cycle management". There are many things that are created for users, departments, and services that, all too often, are left unmanaged. Some examples: user accounts groups SSL certificates access rights databases software license provisionings storage list-serve accounts These objects are created and managed by a wide variety of applications and systems. Typically, a user (person) requests (either explicitly or implicitly) one of these objects. A centralized management tool would help us manage such administration chores as: What objects does user X currently own/manage? Move the ownership of object P to user X; move all objects owned by user X (who was just been fired) to user Y. For all objects of type T that have expired be sure the objects have been disabled or deleted by their provider. How many active (expired, about-to-expire) objects of type P are there? Send periodic notifications to all users who own active objects of type P reminding them of what they own. There is a security alert for objects of type P; send a notification to all users who own these types of objects to take a specific remedial action. Delete or disable a set of objects based on expiration (or some other criteria). These objects are directly managed through their own applications (Active Directory, MySql, file systems, etc.) and may even have their own notification systems, but I want to centralize this into an "object management system". The OMS should allow the association with an external identity provider that defines who the users and groups are (e.g., LDAP, Active Directory) creation of objects association of an object to a specific user and/or group association with an expiration date creation of flexible reporting including letting users know what objects they currently own and their expiration dates integration with an external object "provider" via a plug-in We could write something from scratch, but I am hoping there is something already out there that will help, either an entire application or a set of libraries that provide much of what is needed. Any ideas?

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• Is there a cheaper non-express non-student, non-msdn version of Visual Studio 2010 that supports plugins in the US than the $710 Professional Edition?

  - by Justin Dearing

  I've never actually purchased a copy of Visual Studio myself. SharpDevelop and Express edition have always been good enough for my personal use, and my employers always furnished me with the IDEs I needed to serve them. However, I'm thinking of actually paying for a copy for my personal laptop. I need this mainly so I can open solutions that contain web projects. So my question is: Is there an edition cheaper than the $710 Pro edition on Amazon that will do what I need: http://www.amazon.com/Microsoft-C5E-00521-Visual-Studio-Professional/dp/B0038KTO8S/ref=sr_1_2?ie=UTF8&qid=1287456230&sr=8-2 ? What I need is defined as: Open up a solution with C#, Web App, VB.NET, and Web Projects. Install addins like resharper, testdriven.net, etc, SCM plugins, etc. Some level of db project support. At least to be able to open a dbproj. I only need that for SCM hooks. SSMS and SQLCMD are good enough for actually editing databases. Ability to install F#, IronPython, IronRuby etc. Now naturally I'm a fairly intelligent resourceful person so I realize I can get Visual Studio in a questionable manner. Thats not what I'm looking to do. I want a legal copy, I don't want a student copy, or an MSDN copy. I want a real copy, I just want to make sure I get the cheapest edition that serves my needs.

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• Is there a canonical source supporting "all-surrogates"?

  - by user61852

  Background The "all-PK-must-be-surrogates" approach is not present in Codd's Relational Model or any SQL Standard (ANSI, ISO or other). Canonical books seems to elude this restrictions too. Oracle's own data dictionary scheme uses natural keys in some tables and surrogate keys in other tables. I mention this because these people must know a thing or two about RDBMS design. PPDM (Professional Petroleum Data Management Association) recommend the same canonical books do: Use surrogate keys as primary keys when: There are no natural or business keys Natural or business keys are bad ( change often ) The value of natural or business key is not known at the time of inserting record Multicolumn natural keys ( usually several FK ) exceed three columns, which makes joins too verbose. Also I have not found canonical source that says natural keys need to be immutable. All I find is that they need to be very estable, i.e need to be changed only in very rare ocassions, if ever. I mention PPDM because these people must know a thing or two about RDBMS design too. The origins of the "all-surrogates" approach seems to come from recommendations from some ORM frameworks. It's true that the approach allows for rapid database modeling by not having to do much business analysis, but at the expense of maintainability and readability of the SQL code. Much prevision is made for something that may or may not happen in the future ( the natural PK changed so we will have to use the RDBMS cascade update funtionality ) at the expense of day-to-day task like having to join more tables in every query and having to write code for importing data between databases, an otherwise very strightfoward procedure (due to the need to avoid PK colisions and having to create stage/equivalence tables beforehand ). Other argument is that indexes based on integers are faster, but that has to be supported with benchmarks. Obviously, long, varying varchars are not good for PK. But indexes based on short, fix-length varchar are almost as fast as integers. The questions - Is there any canonical source that supports the "all-PK-must-be-surrogates" approach ? - Has Codd's relational model been superceded by a newer relational model ?

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• SQL Server Database Settings

  - by rbishop

  For those using Data Relationship Management on Oracle DB this does not apply, but for those using Microsoft SQL Server it is highly recommended that you run with Snapshot Isolation Mode. The Data Governance module will not function correctly without this mode enabled. All new Data Relationship Management repositories are created with this mode enabled by default. This mode makes SQL Server (2005+) behave more like Oracle DB where readers simply see older versions of rows while a write is in progress, instead of readers being blocked by locks while a write takes place. Many common sources of deadlocks are eliminated. For example, if one user starts a 5 minute transaction updating half the rows in a table, without snapshot isolation everyone else reading the table will be blocked waiting. With snapshot isolation, they will see the rows as they were before the write transaction started. Conversely, if the readers had started first, the writer won't be stuck waiting for them to finish reading... the writes can begin immediately without affecting the current transactions. To make this change, make sure no one is using the target database (eg: put it into single-user mode), then run these commands: ALTER DATABASE [DB] SET ALLOW_SNAPSHOT_ISOLATION ONALTER DATABASE [DB] SET READ_COMMITTED_SNAPSHOT ON Please make sure you coordinate with your DBA team to ensure tempdb is appropriately setup to support snapshot isolation mode, as the extra row versions are stored in tempdb until the transactions are committed. Let me take this opportunity to extremely strongly highly recommend that you use solid state storage for your databases with appropriate iSCSI, FiberChannel, or SAN bandwidth. The performance gains are significant and there is no excuse for not using 100% solid state storage in 2013. Actually unless you need to store petabytes of archival data, there is no excuse for using hard drives in any systems, whether laptops, desktops, application servers, or database servers. The productivity benefits alone are tremendous, not to mention power consumption, heat, etc.

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• Oracle NoSQL Database: Cleaner Performance

  - by Charles Lamb

  In an earlier post I noted that Berkeley DB Java Edition cleaner performance had improved significantly in release 5.x. From an Oracle NoSQL Database point of view, this is important because Berkeley DB Java Edition is the core storage engine for Oracle NoSQL Database. Many contemporary NoSQL Databases utilize log based (i.e. append-only) storage systems and it is well-understood that these architectures also require a "cleaning" or "compaction" mechanism (effectively a garbage collector) to free up unused space. 10 years ago when we set out to write a new Berkeley DB storage architecture for the BDB Java Edition ("JE") we knew that the corresponding compaction mechanism would take years to perfect. "Cleaning", or GC, is a hard problem to solve and it has taken all of those years of experience, bug fixes, tuning exercises, user deployment, and user feedback to bring it to the mature point it is at today. Reports like Vinoth Chandar's where he observes a 20x improvement validate the maturity of JE's cleaner. Cleaner performance has a direct impact on predictability and throughput in Oracle NoSQL Database. A cleaner that is too aggressive will consume too many resources and negatively affect system throughput. A cleaner that is not aggressive enough will allow the disk storage to become inefficient over time. It has to Work well out of the box, and Needs to be configurable so that customers can tune it for their specific workloads and requirements. The JE Cleaner has been field tested in production for many years managing instances with hundreds of GBs to TBs of data. The maturity of the cleaner and the entire underlying JE storage system is one of the key advantages that Oracle NoSQL Database brings to the table -- we haven't had to reinvent the wheel.

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• How to do a 3-tier using PHP [closed]

  - by Ric

  I have a requirement from a client for my PHP Web application to be 3-tier. For example, I would have a web server on Apache in the DMZ, but it should NOT contain any DB connections. It should connect to a Middle server that would host the business objects but be behind the firewall. Then those objects connect to my SQL cluster on another server. I have actually done this using .NET, but I am not sure how to setup my stack using PHP. I suppose I could have my UI front tier call the middle tier using REST based web services if I create my middle tier as a second web server, but this seems overly complex. The main reason for this is advanced security: we can not have any passwords on the DMZ first tier web server. The second reason is scalability - to have multiple server on different tiers that can handle the requests. The Last reason is for deployment - it is easier if I can take one set of servers offline for testing before putting them back in production. Is there a open source project that shows how to do this? The only example I can find is the web server hosting files from a shared drive on another machine (kind of how DotNetNuke pretends to be 3-tier), but that is NOT secure.

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• Disaster Recovery Example

  Previously, I use to work for a small internet company that sells dental plans online. Our primary focus concerning disaster prevention and recovery is on our corporate website and private intranet site. We had a multiphase disaster recovery plan that includes data redundancy, load balancing, and off-site monitoring. Data redundancy is a key aspect of our disaster recovery plan. The first phase of this is to replicate our data to multiple database servers and schedule daily backups of the databases that are stored off site. The next phase is the file replication of data amongst our web servers that are also backed up daily by our collocation. In addition to the files located on the server, files are also stored locally on development machines, and again backed up using version control software. Load balancing is another key aspect of our disaster recovery plan. Load balancing offers many benefits for our system, better performance, load distribution and increased availability. With our servers behind a load balancer our system has the ability to accept multiple requests simultaneously because the load is split between multiple servers. Plus if one server is slow or experiencing a failure the traffic is diverted amongst the other servers connected to the load balancer allowing the server to get back online. The final key to our disaster recovery plan is off-site monitoring that notifies all IT staff of any outages or errors on the main website encountered by the monitor. Messages are sent by email, voicemail, and SMS. According to Disasterrecovery.org, disaster recovery planning is the way companies successfully manage crises with minimal cost and effort and maximum speed compared to others that are forced to make decision out of desperation when disasters occur. In addition Sun Guard stated in 2009 that the first step in disaster recovery planning is to analyze company risks and factor in fixed costs for things like hardware, software, staffing and utilities, as well as indirect costs, such as floor space, power protection, physical and information security, and management. Also availability requirements need to be determined per application and system as well as the strategies for recovery.

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• Are injectable classes allowed to have constructor parameters in DI?

  - by Songo

  Given the following code: class ClientClass{ public function print(){ //some code to calculate $inputString $parser= new Parser($inputString); $result= $parser->parse(); } } class Parser{ private $inputString; public __construct($inputString){ $this->inputString=$inputString; } public function parse(){ //some code } } Now the ClientClass has dependency on class Parser. However, if I wanted to use Dependency Injection for unit testing it would cause a problem because now I can't send the input string to the parser constructor like before as its calculated inside ClientCalss itself: class ClientClass{ private $parser; public __construct(Parser $parser){ $this->parser=$parser; } public function print(){ //some code to calculate $inputString $result= $this->parser->parse(); //--> will throw an exception since no string was provided } } The only solution I found was to modify all my classes that took parameters in their constructors to utilize Setters instead (example: setInputString()). However, I think there might be a better solution than this because sometimes modifying existing classes can cause much harm than benefit. So, Are injectable classes not allowed to have input parameters? If a class must take input parameters in its constructor, what would be the way to inject it properly? UPDATE Just for clarification, the problem happens when in my production code I decide to do this: $clientClass= new ClientClass(new Parser($inputString));//--->I have no way to predict $inputString as it is calculated inside `ClientClass` itself. UPDATE 2 Again for clarification, I'm trying to find a general solution to the problem not for this example code only because some of my classes have 2, 3 or 4 parameters in their constructors not only one.

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• How does datomic handle "corrections"?

  - by blueberryfields

  tl;dr Rich Hickey describes datomic as a system which implicitly deals with timestamps associated with data storage from my experience, data is often imperfectly stored in systems, and on many occasions needs to retroactively be corrected (ie, often the question of "was a True on Tuesday at 12:00pm?" will have an incorrect answer stored in the database) This seems like a spot where the abstractions behind datomic might break - do they? If they don't, how does the system handle such corrections? Rich Hickey, in several of his talks, justifies the creation of datomic, and explains its benefits. His work, if I understand correctly, is motivated by core the insight that humans, when speaking about data and facts, implicitly associate some of the related context into their work(a date-time). By pushing the work required to manage the implicit date-time component of context into the database, he's created a system which is both much easier to understand, and much easier to program. This turns out to be relevant to most database programmers in practice - his work saves everyone a lot of time managing complex, hard to produce/debug/fix, time queries. However, especially in large databases, data is often damaged/incorrect (maybe it was not input correctly, maybe it eroded over time, etc...). While most database updates are insertions of new facts, and should indeed be treated that way, a non-trivial subset of the work required to manage time-queries has to do with retroactive updates. I have yet to see any documentation which explains how such corrections, or retroactive updates, are handled by datomic; from my experience, they are a non-trivial (and incredibly difficult to deal with) subset of time-related data manipulation that database programmers are faced with. Does datomic gracefully handle such updates? If so, how?

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