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• Key-Based SSH Permission denied (publickey) Ubuntu 12-04

  - by user125176

  I have configured sshd to accept key-based ssh logins with LogLevel on DEBUG, and uploaded my public key to ~/.ssh.authorized_keys, where permissions are set as: 700 ~/.ssh 600 ~/.ssh/authorized_keys From root, I can su - USERNAME. From the client I get Permission denied (publicly). From the server Here's how it is telling me that it "Could not open authorized keys '/home/USERNAME/.ssh/authorized_keys': Permission denied". Client protocol version 2.0; client software version OpenSSH_5.2 match: OpenSSH_5.2 pat OpenSSH* Enabling compatibility mode for protocol 2.0 Local version string SSH-2.0-OpenSSH_5.9p1 Debian-5ubuntu1 permanently_set_uid: 105/65534 [preauth] list_hostkey_types: ssh-rsa,ssh-dss,ecdsa-sha2-nistp256 [preauth] SSH2_MSG_KEXINIT sent [preauth] SSH2_MSG_KEXINIT received [preauth] kex: client->server aes128-ctr hmac-md5 none [preauth] kex: server->client aes128-ctr hmac-md5 none [preauth] SSH2_MSG_KEX_DH_GEX_REQUEST received [preauth] SSH2_MSG_KEX_DH_GEX_GROUP sent [preauth] expecting SSH2_MSG_KEX_DH_GEX_INIT [preauth] SSH2_MSG_KEX_DH_GEX_REPLY sent [preauth] SSH2_MSG_NEWKEYS sent [preauth] expecting SSH2_MSG_NEWKEYS [preauth] SSH2_MSG_NEWKEYS received [preauth] KEX done [preauth] userauth-request for user USERNAME service ssh-connection method none [preauth] attempt 0 failures 0 [preauth] PAM: initializing for "USERNAME" PAM: setting PAM_RHOST to "USERHOSTNAME" PAM: setting PAM_TTY to "ssh" userauth_send_banner: sent [preauth] userauth-request for user USERNAME service ssh-connection method publickey [preauth] attempt 1 failures 0 [preauth] test whether pkalg/pkblob are acceptable [preauth] Checking blacklist file /usr/share/ssh/blacklist.RSA-4096 Checking blacklist file /etc/ssh/blacklist.RSA-4096 temporarily_use_uid: 1001/1002 (e=0/0) trying public key file /home/USERNAME/.ssh/authorized_keys Could not open authorized keys '/home/USERNAME/.ssh/authorized_keys': Permission denied restore_uid: 0/0 temporarily_use_uid: 1001/1002 (e=0/0) trying public key file /home/USERNAME/.ssh/authorized_keys2 Could not open authorized keys '/home/USERNAME/.ssh/authorized_keys2': Permission denied restore_uid: 0/0 Failed publickey for USERNAME from IPADDRESS port 57523 ssh2 Connection closed by IPADDRESS [preauth] do_cleanup [preauth] monitor_read_log: child log fd closed do_cleanup PAM: cleanup

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• How should I define a composite foreign key for domain constraints in the presence of surrogate keys

  - by Samuel Danielson

  I am writing a new app with Rails so I have an id column on every table. What is the best practice for enforcing domain constraints using foreign keys? I'll outline my thoughts and frustration. Here's what I would imagine as "The Rails Way". It's what I started with. Companies: id: integer, serial company_code: char, unique, not null Invoices: id: integer, serial company_id: integer, not null Products: id: integer, serial sku: char, unique, not null company_id: integer, not null LineItems: id: integer, serial invoice_id: integer, not null, references Invoices (id) product_id: integer, not null, references Products (id) The problem with this is that a product from one company might appear on an invoice for a different company. I added a (company_id: integer, not null) to LineItems, sort of like I'd do if only using natural keys and serials, then added a composite foreign key. LineItems (product_id, company_id) references Products (id, company_id) LineItems (invoice_id, company_id) references Invoices (id, company_id) This properly constrains LineItems to a single company but it seems over-engineered and wrong. company_id in LineItems is extraneous because the surrogate foreign keys are already unique in the foreign table. Postgres requires that I add a unique index for the referenced attributes so I am creating a unique index on (id, company_id) in Products and Invoices, even though id is simply unique. The following table with natural keys and a serial invoice number would not have these issues. LineItems: company_code: char, not null sku: char, not null invoice_id: integer, not null I can ignore the surrogate keys in the LineItems table but this also seems wrong. Why make the database join on char when it has an integer already there to use? Also, doing it exactly like the above would require me to add company_code, a natural foreign key, to Products and Invoices. The compromise... LineItems: company_id: integer, not null sku: integer, not null invoice_id: integer, not null does not require natural foreign keys in other tables but it is still joining on char when there is a integer available. Is there a clean way to enforce domain constraints with foreign keys like God intended, but in the presence of surrogates, without turning the schema and indexes into a complicated mess?

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• Resources on concepts/theory behind GUI development?

  - by ShrimpCrackers

  I was wondering if there were any resources that explain concepts/theory behind GUI development. I don't mean a resource that explains how to use a GUI library, but rather how to create your own widgets. For example a resource that explains different methods on how to implement scrollable listboxes. I ask because I have an idea for a game tool where I would like to create my own widgets and let users drag and drop them onto some kind of form. How do GUI libraries usually draw widgets? I'm not sure if reskinning widgets from a GUI library fits my needs, since widget behavior needs to be dynamic based on user interaction.

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• Primary key/foreign Key naming convention

  - by Jeremy

  In our dev group we have a raging debate regarding the naming convention for Primary and Foreign Keys. There's basically two schools of thought in our group: 1) Primary Table (Employee) Primary Key is called ID Foreign table (Event) Foreign key is called EmployeeID 2) Primary Table (Employee) Primary Key is called EmployeeID Foreign table (Event) Foreign key is called EmployeeID I prefer not to duplicate the name of the table in any of the columns (So I prefer option 1 above). Conceptually, it is consisted with a lot of the recommended practices in other languages, where you don't use the name of the object in its property names. I think that naming the foreign key EmployeeID (or Employee_ID might be better) tells the reader that it is the ID column of the Employee Table. Some others prefer option 2 where you name the primary key prefixed with the table name so that the column name is the same throughout the database. I see that point, but you now can not visually distinguish a primary key from a foreign key. Also, I think it's redundant to have the table name in the column name, because if you think of the table as an entity and a column as a property or attribute of that entity, you think of it as the ID attribute of the Employee, not the EmployeeID attribute of an employee. I don't go an ask my coworker what his PersonAge or PersonGender is. I ask him what his Age is. So like I said, it's a raging debate and we go on and on and on about it. I'm interested to get some new perspective.

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• Key Windows Phone Development Concepts

  - by Tim Murphy

  As I am doing more development in and out of the enterprise arena for Windows Phone I decide I would study for the 70-599 test.  I generally take certification tests as a way to force me to dig deeper into a technology.  Between the development and studying I decided it would be good to put a post together of key development features in Windows Phone 7 environment.  Contrary to popular belief the launch of Windows Phone 8 will not obsolete Windows Phone 7 development.  With the launch of 7.8 coming shortly and people who will remain on 7.X for the foreseeable future there are still consumers needing these apps so don’t throw out the baby with the bath water. PhoneApplicationService This is a class that every Windows Phone developer needs to become familiar with.  When it comes to application state this is your go to repository.  It also contains events that help with management of your application’s lifecycle.  You can access it like the following code sample. 1: PhoneApplicationService.Current.State["ValidUser"] = userResult; DeviceNetworkInformation This class allows you to determine the connectivity of the device and be notified when something changes with that connectivity.  If you are making web service calls you will want to check here before firing off. I have found that this class doesn’t actually work very well for determining if you have internet access.  You are better of using the following code where IsConnectedToInternet is an App level property. private void Application_Launching(object sender, LaunchingEventArgs e){ // Validate user access if (Microsoft.Phone.Net.NetworkInformation.NetworkInterface.NetworkInterfaceType != Microsoft.Phone.Net.NetworkInformation.NetworkInterfaceType.None) { IsConnectedToInternet = true; } else { IsConnectedToInternet = false; } NetworkChange.NetworkAddressChanged += new NetworkAddressChangedEventHandler(NetworkChange_NetworkAddressChanged);}void NetworkChange_NetworkAddressChanged(object sender, EventArgs e){ IsConnectedToInternet = (Microsoft.Phone.Net.NetworkInformation.NetworkInterface.NetworkInterfaceType != Microsoft.Phone.Net.NetworkInformation.NetworkInterfaceType.None);} Push Notification Push notification allows your application to receive notifications in a way that reduces the application’s power needs. This MSDN article is a good place to get the basics of push notification, but you can see the essential concept in the diagram below.  There are three types of push notification: toast, Tile and raw.  The first two work regardless of the state of the application where as raw messages are discarded if your application is not running.   Live Tiles Live tiles are one of the main differentiators of the Windows Phone platform.  They allow users to find information at a glance from their start screen without navigating into individual apps.  Knowing how to implement them can be a great boost to the attractiveness of your application. The simplest step-by-step explanation for creating live tiles is here. Local Database While your application really only has Isolated Storage as a data store there are some ways of giving you database functionality to develop against.  There are a number of open source ORM style solutions.  Probably the best and most native way I have found is to use LINQ to SQL.  It does take a significant amount of setup, but the ease of use once it is configured is worth the cost.  Rather than repeat the full concepts here I will point you to a post that I wrote previously. Tasks (Bing, Email) Leveraging built in features of the Windows Phone platform is an easy way to add functionality that would be expensive to develop on your own.  The classes that you need to make yourself familiar with are BingMapsDirectionsTask and EmailComposeTask.  This will allow your application to supply directions and give the user an email path to relay information to friends and associates. Event model Because of the ability for users to switch quickly to switch to other apps or the home screen is just one reason why knowing the Windows Phone event model is important.  You need to be able to save data so that if a user gets a phone call they can come back to exactly where they were in your application.  This means that you will need to handle such events as Launching, Activated, Deactivated and Closing at an application level.  You will probably also want to get familiar with the OnNavigatedTo and OnNavigatedFrom events at the page level.  These will give you an opportunity to save data as a user navigates through your app. Summary This is just a small portion of the concepts that you will use while building Windows Phone apps, but these are some of the most critical.  With the launch of Windows Phone 8 this list will probably expand.  Take the time to investigate these topics further and try them out in your apps. del.icio.us Tags: Windows Phone 7,Windows Phone,WP7,Software Development,70-599

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• mysql ON DUPLICATE KEY UPDATE

  - by julio

  Hi-- I'm stuck on a mySQL query using ON DUPLICATE KEY UPDATE. I'm getting the error: mySQL Error: 1062 - Duplicate entry 'hr2461809-3' for key 'fname' The table looks like this: id int(10) NOT NULL default '0', picid int(10) unsigned NOT NULL default '0', fname varchar(255) NOT NULL default '', type varchar(5) NOT NULL default '.jpg', path varchar(255) NOT NULL default '', PRIMARY KEY (id), UNIQUE KEY fname (fname), KEY picid (propid) ) ENGINE=MyISAM DEFAULT CHARSET=utf8; And the query that's breaking is this: INSERT INTO images SET picid=732, fname='hr2461809-3', path='pictures/' ON DUPLICATE KEY UPDATE picid=732, fname='hr2461809-3', path='pictures/' I'm using a very similar query elsewhere in the app with no issues. I'm not sure why this one breaks. I expected that when the UNIQUE KEY on fname gets violated, that it would simply update the row where the violation occurred? Thanks for any help

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• Windows XP Product Key for SP3 installation

  - by Ham

  I have an somewhat older Notebook with an original Windows XP Professional License Sticker underneath. This Notebook was erased completely once and now I want to install a new Windows XP Professional System on it using the key that's on the sticker. But there seems to be one problem: I am using an Windows XP Professional SP3 image I got from my university (thanks to MSDNAA). But somehow I cannot use the license key on the sticker with this installation. It keeps saying that this key is invalid. What can I do? Is this because I try to install a Win XP Professional with SP3 directly? Do I need another image to install this?

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• Audit Windows Server/Desktop Product Key usage

  - by neildeadman

  The company I work for has a fairly big domain of Windows Desktops and Servers. We also have standalone servers that are remote to our site but we have direct access to. We need to audit our license usage across all Windows machines (including some VMs). I have tried a few products downloaded, but the key returned is not the one used during installation. I have one product that gives the last 5 characters correctly but needs to be installed so its not really suitable. I also have tried some PowerShell scripts one of which is here Ideally I am looking for one that can be used over a network and if possible can audit Office keys too. I've just tried Jelly Bean and some other product key tools that all return BBBBB-BBBBB-BBBBB-BBBB-BBBBB as the product key.

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• SQL Server 2008 Registration with Product Key

  - by Kanini

  A colleague of mine gave me the SQL Server 2008 Standard ISO image and I used that while building a Virtual Machine. Now, when I installed SQL Server with that above mentioned ISO, I did not give it a key and I chose Enterprise Evaluation. So, the instance has now been activated with 180-day expiration. I do have a valid MSDN Subscriber login but when I login and search for SQL Server 2008 it comes up with the download but says No Product Key is required. How do I now enter the product key?

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• Checking whether product key will work with SBS 2003

  - by Rob Nicholson

  We've recently absorbed a small company who had a Dell PowerEdge server running SBS 2003. For some reason, the hard disks have been wiped. We have the product key though from the sticker on the side of the case but not the installation media: Win SBS Std 2003 1-2 CPU 5-CAL OEM software We do have a Dell labelled set of four CDs labelled SBS 2003 in our store and I've built a VM from this media but it doesn't prompt for the product key during install. Is there any way to ascertain whether this media will work with this product key without going through activation? I know one can activate several times but would prefer to check we've got the right media before doing this. Thanks, Rob.

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• SSH rsa key works with external IP not internal IP

  - by Ian

  I am using rackspace cloud hosting. I have 2 servers behind a load balancer. Each server has an external IP and an internal IP. I want to setup a sync job that uses SSH to transfer files. I made an rsa key, and I can successfully SSH from server A into server B, using the external IP of server B, without being prompted for a password. If I try to do the same but use the internal IP, it prompts me for a password. I want to be able to use the key instead of the password. Why is this? Is there something special I have to do during key generation so it works for both IPs? Any help is appreciated.

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• How can I know which key of Windows Vista corresponds to the upgrade key of Windows 7

  - by js_

  I have two Dell PCs. And each PC has a Windows Vista disc and a Windows 7 upgrade disc which Dell gave me for free. And each disc has a product key. There are 4 product keys in total. I'm going to sell one of the Dell PCs. But unfortunately I don't know which product key of Windows 7 corresponds to which product key of Windows Vista. If I sell the PC with wrong combination of a Windows Vista and a Windows 7, error will occur and I will get in trouble. How can I know which Windows 7 corresponds to which Windows Vista?

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• How to map Ctrl + ',' to greater key( '>') or Ctrl + '.' to less key( '<' ) using xmodmap?

  - by Maxrunner

  So im trying to creating a combination of keys to generate the ISO key for Portuguese layout, the key in question is the <, pressing it normally will generate the '<' character, pressing + shift will generate the ' ' character. So i'm trying to create a combination while using xmodmap, and i want this to work for all programs.I've been searching on Google and came up with this example for Control + P = Up: Control + p = Up arrow example The example for that behaviour is: xmodmap -e "keycode 33 = p P Up" keycode 33 matches the p key, so where does control comes up in that command? regards,

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• Public key repository - does this exist?

  - by allegroconmolto

  This is one of those "Surely this already exists, and if not, I damn well better build it!" moments. Here's my problem: I run a devteam, of around 10 individuals. Each of us has our own private key(s). When I go set up a new server for us, I have to import all of their keys to it. And if we start working with a contractor, I have to get his or her key too, and then import it and place it in .ssh/authorized_keys on the server. Ideally I'd like to be able to do something along the lines of: import_key allegroconmolto And it would contact a public repository of public keys, see if there was a user named allegroconmolto, and if so, import their key and add it to my authorized_keys. Adding future users would then be as simple as running import_key for them. I could then scp the authorized_keys file to all my servers and be done! This seems so obvious that I feel like it surely must exist somewhere.

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• What does "Controller Key" mean in Interface Builder > Inspector > Bindings?

  - by Thanks

  I can't find in the Docs where they explain all those fields and what they mean. Especially "Controller Key" is not clear to me.

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• Extracting public key from private key in OpenSSL

  - by ereOn

  Hello, I need to extract the RSA public key from a RSA private key using OpenSSL. I'm currently using RSAPublicKey_dup() passing the RSA* private key to get the public key. However, while the call seems to work, I cannot load (or use) this public key using the openssl command-line tool. If I generate the public key using the command-line tool ("$ openssl rsa -in private.pem -pubout > public.pem"), I can use it and it works like a charm. Do you guys know how I can get this work ? Maybe another function ? The OpenSSL documentation is quite hard to browse... Thank you.

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• Emacs: print key binding for a command or list all key bindings

  - by Yktula

  In Emacs (GNU 23.2, *nix), how can I: list the key sequences bound to a particular command? For example, how can we list all the key sequences that execute save-buffers-kill-emacs, with the output of key sequences bound to it? Assuming we can do this, listing the key sequences bound to goto-line should print the output: M-g g on a default install. list all key-bindings? Does C-h b do this? Would it print my own bindings? I am aware that executing the command directly can print a key sequence it can be activated with, but it doesn't always do so, and a few things happen, including: (1) the output doesn't remain for long, (2) the command is executed. I want a command that lists for me (preferably all) the bindings attached to a given command, without executing the command, or something like that.

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• JRockit Virtual Edition Debug Key

  - by changjae.lee

  There are a few keys that can help the debugging of the JRVE env in console. you can type in each keys in JRVE console to see what's happening under the hood. key '0' : System information key '5' : Enable shutdown key '7' : Start JRockit Management Server (port 7091) key '8' : Statistics Counters key '9' : Full Thread Dump key '0' : Status of Debug-key Below is the sample out from each keys. Debug-key '1' pressed ============ JRockitVE System Information ============ JRockitVE version : 11.1.1.3.0-67-131044 Kernel version : 6.1.0.0-97-131024 JVM version : R27.6.6-28_o-125824-1.6.0_17-20091214-2104-linux-ia32 Hypervisor version : Xen 3.4.0 Boot state : 0x007effff Uptime : 0 days 02:04:31 CPU : uniprocessor @2327 Mhz CPU usage : 0% ctx/s: 285 preempt/s: 0 migrations/s: 0 Physical pages : 82379/261121 (321/1020 MB) Network info : 10.179.97.64 (10.179.97.64/255.255.254.0) GateWay : 10.179.96.1 MAC address : 00:16:3e:7e:dc:78 Boot options : vfsCwd : /application/user_projects/domains/wlsve_domain mainArgs : java -javaagent:/jrockitve/services/sshd/sshd.jar -cp /jrockitve/jrockit/lib/tools.jar:/jrockitve/lib/common.jar:/application/patch_wls1032/profiles/default/sys_manifest_classpath/weblogic_patch.jar:/application/wlserver_10.3/server/lib/weblogic.jar -Dweblogic.Name=WlsveAdmin -Dweblogic.Domain=wlsve_domain -Dweblogic.management.username=weblogic -Dweblogic.management.password=welcome1 -Dweblogic.management.GenerateDefaultConfig=true weblogic.Server consLog : /jrockitve/log/jrockitve.log mounts : ext2 / dev0; posixLocale : en_US posixTimezone : Asia/Seoul posixEncoding : ISO-8859-1 Local disk : Size: 1024M, Used: 728M, Free: 295M ======================================================== Debug-key '5' pressed Shutdown enabled. Debug-key '7' pressed [JRockit] Management server already started. Ignoring request. Debug-key '8' pressed Starting stat recording Debug-key '8' pressed ========= Statistics Counters for the last second ========= dev.eth0_rx.cnt : 22 packets dev.eth0_rx_bytes.cnt : 2704 bytes dev.net_interrupts.cnt : 22 interrupts evt.timer_ticks.cnt : 123 ticks hyper.priv_entries.cnt : 144 entries schedule.context_switches.cnt : 271 switches schedule.idle_cpu_time.cnt : 997318849 nanoseconds schedule.idle_cpu_time_0.cnt : 997318849 nanoseconds schedule.total_cpu_time.cnt : 1000031757 nanoseconds time.system_time.cnt : 1000 ns time.timer_updates.cnt : 123 updates time.wallclock_time.cnt : 1000 ns ======================================= Debug-key '9' pressed ===== FULL THREAD DUMP =============== Fri Jun 4 08:22:12 2010 BEA JRockit(R) R27.6.6-28_o-125824-1.6.0_17-20091214-2104-linux-ia32 "Main Thread" id=1 idx=0x4 tid=1 prio=5 alive, in native, waiting -- Waiting for notification on: weblogic/t3/srvr/T3Srvr@0x646ede8[fat lock] at jrockit/vm/Threads.waitForNotifySignal(JLjava/lang/Object;)Z(Native Method) at java/lang/Object.wait(J)V(Native Method) at java/lang/Object.wait(Object.java:485) at weblogic/t3/srvr/T3Srvr.waitForDeath(T3Srvr.java:919) ^-- Lock released while waiting: weblogic/t3/srvr/T3Srvr@0x646ede8[fat lock] at weblogic/t3/srvr/T3Srvr.run(T3Srvr.java:479) at weblogic/Server.main(Server.java:67) at jrockit/vm/RNI.c2java(IIIII)V(Native Method) -- end of trace "(Signal Handler)" id=2 idx=0x8 tid=2 prio=5 alive, in native, daemon Open lock chains ================ Chain 1: "ExecuteThread: '0' for queue: 'weblogic.socket.Muxer'" id=23 idx=0x50 tid=20 waiting for java/lang/String@0x630c588 held by: "ExecuteThread: '1' for queue: 'weblogic.socket.Muxer'" id=24 idx=0x54 tid=21 (active) ===== END OF THREAD DUMP =============== Debug-key '0' pressed Debug-keys enabled Happy Cloud Walking :)

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• How do I replicate the Super Key?

  - by joemangrove

  If you use xmonad, xbindkeys, and xdotool to try and remap the 'Menu' key, it does not work perfectly. The 'Menu' key will only emulate the Super key's quick press action, bringing up the application search. If you hold in the 'Menu' key it will not emulate the Super key's hold down action. That is, bring up the launcer with numbers over the applications. How do you make another key on the keyboard act exactly like the Super key?

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• Numpad's Enter key is acting like the Command key instead

  - by user19294

  I can't get the numpad Enter key to work on OS X 10.6.5. The numpad works fine, as do the plus and minus keys. Only the Enter is not working. I tried 2 keyboards and I get the same problem with both, so it's got to be a setting somewhere. In Keyboard Viewer, when I press the key, it shows that the ? keys are pressed. And indeed, pressing Enter-L puts the cursor in the location bar of my browser, just like Command-L would. Is there a way to remap it?

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• Programming concepts taken from the arts and humanities

  - by Joey Adams

  After reading Paul Graham's essay Hackers and Painters and Joel Spolsky's Advice for Computer Science College Students, I think I've finally gotten it through my thick skull that I should not be loath to work hard in academic courses that aren't "programming" or "computer science" courses. To quote the former: I've found that the best sources of ideas are not the other fields that have the word "computer" in their names, but the other fields inhabited by makers. Painting has been a much richer source of ideas than the theory of computation. — Paul Graham, "Hackers and Painters" There are certainly other, much stronger reasons to work hard in the "boring" classes. However, it'd also be neat to know that these classes may someday inspire me in programming. My question is: what are some specific examples where ideas from literature, art, humanities, philosophy, and other fields made their way into programming? In particular, ideas that weren't obviously applied the way they were meant to (like most math and domain-specific knowledge), but instead gave utterance or inspiration to a program's design and choice of names. Good examples: The term endian comes from Gulliver's Travels by Tom Swift (see here), where it refers to the trivial matter of which side people crack open their eggs. The terms journal and transaction refer to nearly identical concepts in both filesystem design and double-entry bookkeeping (financial accounting). mkfs.ext2 even says: Writing superblocks and filesystem accounting information: done Off-topic: Learning to write English well is important, as it enables a programmer to document and evangelize his/her software, as well as appear competent to other programmers online. Trigonometry is used in 2D and 3D games to implement rotation and direction aspects. Knowing finance will come in handy if you want to write an accounting package. Knowing XYZ will come in handy if you want to write an XYZ package. Arguably on-topic: The Monad class in Haskell is based on a concept by the same name from category theory. Actually, Monads in Haskell are monads in the category of Haskell types and functions. Whatever that means...

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• Vernon's book Implementing DDD and modeling of underlying concepts

  - by EdvRusj

  Following questions all refer to examples presented in Implementing DDD In article we can see from Figure 6 that both BankingAccount and PayeeAccount represent the same underlying concept of Banking Account BA 1. On page 64 author gives an example of a publishing organization, where the life-cycle of a book goes through several stages ( proposing a book, editorial process, translation of the book ... ) and at each of those stages this book has a different definition. Each stage of the book is defined in a different Bounded Context, but do all these different definitions still represent the same underlying concept of a Book, just like both BankingAccount and PayeeAccount represent the same underlying concept of a BA? 2. a) I understand why User shouldn't exist in Collaboration Context ( CC ), but instead should be defined within Identity and Access Context IAC ( page 65 ). But still, do User ( IAC ), Moderator ( CC ), Author ( CC ),Owner ( CC ) and Participant ( CC ) all represent different aspects of the same underlying concept? b) If yes, then this means that CC contains several model elements ( Moderator, Author, Owner and Participant ), each representing different aspect of the same underlying concept ( just like both BankingAccount and PayeeAccount represent the same underlying concept of a BA ). But isn't this considered a duplication of concepts ( Evan's book, page 339 ), since several model elements in CC represent the same underlying concept? c) If Moderator, Author ... don't represent the same underlying concept, then what underlying concept does each represent? 3. In an e-commerce system, the term Customer has multiple meanings ( page 49 ): When user is browsing the Catalog, Customer has different meaning than when user is placing an Order. But do these two different definitions of a Customer represent the same underlying concept, just like both BankingAccount and PayeeAccount represent the same underlying concept of a BA? thanks

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• How can I Duplicate a MSSQL Symmetric Key?

  - by rlb.usa

  We have a server with a database that has a symmetric key (Database - Security - Symmetric Key). We have a backup duplicate databases that we are using as a test databases, but we don't have this key in there. How can I duplicate this symmetric key (or make a new one exactly like the old) and put it in the existing databases? It has to have the same value and key-name as the other one. This is on MS SQL Server (edit) 2008 .

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• How do I Duplicate a MSSQL Symmetric Key

  - by rlb.usa

  We have a server with a database that has a symmetric key (Database - Security - Symmetric Key). We have a backup duplicate databases that we are using as a test databases, but we don't have this key in there. How can I duplicate this symmetric key and put it in the existing databases? It has to have the same value and key-name as the other one. This is on MS SQL Server 2008 .

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• What mail storage should I choose for our web application; IMAP, key-valud store, rdbms, ...

  - by tvrtko

  I have to store e-mail messages for use with our application. I have "metadata" for all messages inside a relational database, but I don't feel comfortable keeping message content (gigabytes and terabytes of email data) inside a database. I'm currently using IMAP as a storage, but I have my doubts if I choose correctly. First of all there is a problem of uidvalidity and how to keep a permanent reference to message inside IMAP. Second, I'm not sure if this is the most robust solution in terms of backup/restore strategies, corruption of store, replication ... Positive side is that I can query IMAP using the headers because the data is mostly indexed. I don't know if key-value stores are a better approach (Casandra, Tokyo cabinet, redis). How they handle storing 1KB and 50MB of data. How they prevent corruption and when corruption or device failure happens how can I repair the store.

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