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  • Oracle JDBC connection with Weblogic 10 datasource mapping, giving problem java.sql.SQLException: Cl

    - by gauravkarnatak
    Oracle JDBC connection with Weblogic 10 datasource mapping, giving problem java.sql.SQLException: Closed Connection I am using weblogic 10 JNDI datasource to create JDBC connections, below is my config http://www.bea.com/ns/weblogic/920.xsd" XL-Reference-DS jdbc:oracle:oci:@abc.XL.COM oracle.jdbc.driver.OracleDriver user DEV_260908 password password dll ocijdbc10 protocol oci oracle.jdbc.V8Compatible true baseDriverClass oracle.jdbc.driver.OracleDriver 1 100 1 true SQL SELECT 1 FROM DUAL ReferenceData OnePhaseCommit When I run a bulk task where there are lotsa connection made and closed, sometimes it gives connection closed exception for any of the task in the bulk task. Below is detailed exception' java.sql.SQLException: Closed Connection at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:111) at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:145) at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:207) at oracle.jdbc.driver.OracleStatement.ensureOpen(OracleStatement.java:3512) at oracle.jdbc.driver.OraclePreparedStatement.executeInternal(OraclePreparedStatement.java:3265) at oracle.jdbc.driver.OraclePreparedStatement.executeUpdate(OraclePreparedStatement.java:3367) Any pointers ? Thanks in advance, Gaurav

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  • Forth: free video tutorials?

    - by Peter Mortensen
    Can you recommend any free Forth video tutorials (except for following) ? The only one I know of is Samuel A. Falvo's excellent "Over The Shoulder Episode 1: Text Preprocessing in Forth". MPEG. 102 MB. There are also videos from the annual Forth Day, but I don't consider those to be tutorials. (Unfortunately Forth is, like R, C, C++, Java, C#, D, COM, .NET, F# and Frontier, an unspecific search term. Search tip for Forth: qualify it with "ans" - as in ANS Forth, the ANSI Forth Standard.) Accumulated based on answers and other information: Introductions to Forth Forth. By Ben Stiglitz. At RubyConf 2008 Orlando Florida, U.S.A. 13 min 35 secs. 32 MB. MP4. Advanced Over The Shoulder Episode 1: Text Preprocessing in Forth. By Samuel A. Falvo. 1 h 06 min 25 secs. 102 MB. MPEG.

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  • Problem in calling Excel function

    - by Newbie
    I am facing a problem while making Excel's LinEST function. My program goes like MyExcel.Application xl = new MyExcel.Application(); MyExcel.WorksheetFunction wsf = xl.WorksheetFunction; List<int> x = new List<int> { 1, 2, 3, 4 }; List<int> y = new List<int> { 11, 12, 45, 42 }; object o = wsf.LinEst(x, y, true, true); And the namespace is using MyExcel = Microsoft.Office.Interop.Excel; The program is compiling smoothly but at runtime it is throwing an error {System.Runtime.InteropServices.COMException (0x80020005): Type mismatch. (Exception from HRESULT: 0x80020005 (DISP_E_TYPEMISMATCH)) Actually this is the first time I am using Excel function .. so I am unable to proceed further. If any one has run thru this kind of situation and has solved, please help me. I am using C# 3.0 Thanks

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  • printing multi dimentional array

    - by Honey
    i have this multi dimentional array that i want to print into a table having each record/item go into its own row but it goes column wise. this is the output that im getting: http://mypetshopping.com/product.php ps: the value of $product will by dynamic based on what product is being viewed. <?php session_start(); ?> <table> <thead> <tr> <th>Name</th> <th>Hash</th> <th>Quantity</th> <th>Size</th> <th>Color</th> </tr> </thead> <tbody> <?php function addCart($product, $quantity, $size,$color) { $hash = md5($product); $_SESSION['cart'][$product]['name'] = $product; $_SESSION['cart'][$product]['hash'] = $hash; $_SESSION['cart'][$product]['quantity'] = $quantity; $_SESSION['cart'][$product]['size'] = $size; $_SESSION['cart'][$product]['color'] = $color; } addCart('Red Dress',1,'XL','red'); addCart('Blue Dress',1,'XL','blue'); addCart('Slippers',1,'XL','orange'); addCart('Green Hat',1,'XXXL','green'); $cart = $_SESSION['cart']; foreach($cart as $product => $array) { foreach($array as $key => $value) { ?> <tr> <td><?=$value;?></td> <td><?=$value;?></td> <td><?=$value;?></td> <td><?=$value;?></td> <td><?=$value;?></td> </tr> <?php } } ?>

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  • Why can't set cast an object from Excel interop?

    - by AngryHacker
    Trying to get a reference to the worksheets (using Excel interop): Excel.Application xl = new Excel.ApplicationClass(); Excel.Workbooks xlWorkBooks = xl.Workbooks; Excel.Workbook xlWorkBook = xlWorkBooks.Open(fileName, 0, false, 5, "", "", true, Excel.XlPlatform.xlWindows, "\t", false, false, 0, true, 1, 0); Excel.Worksheets xlWorkSheets = (Excel.Worksheets) xlWorkBook.Worksheets; // crashes The error is that it cannot cast it: Unable to cast COM object of type 'System.__ComObject' to interface type 'Microsoft.Office.Interop.Excel.Worksheets'. This operation failed because the QueryInterface call on the COM component for the interface with IID '{000208B1-0000-0000-C000-000000000046}' failed due to the following error: No such interface supported (Exception from HRESULT: 0x80004002 (E_NOINTERFACE)). Is my cast incorrect?

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  • Guaranteed COM object release?

    - by Jurily
    I wrote the following code under the assumption that Excel will die with Monkey: class ExcelMonkey { private static Excel.Application xl = new Excel.Application(); public static bool parse(string filename) { if (filename.Contains("foo")) { var workbook = xl.Workbooks.Open(filename); var sheet = workbook.Worksheets.get_Item(1); // do stuff return true; } return false; } } How do I make sure it does? Do I need to release workbook and sheet separately? I want to have Excel around for the lifetime of the program, it's a huge performance improvement.

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  • Parsing XML data with Namespaces in PHP

    - by osbmedia
    I'm trying to work with this XML feed that uses namespaces and i'm not able to get past the colon in the tags. Here's how the XML feed looks like: <r25:events pubdate="2010-05-19T13:58:08-04:00"> <r25:event xl:href="event.xml?event_id=328" id="BRJDMzI4" crc="00000022" status="est"> <r25:event_id>328</r25:event_id> <r25:event_name>Testing 09/2005-08/2006</r25:event_name> <r25:alien_uid/> <r25:event_priority>0</r25:event_priority> <r25:event_type_id xl:href="evtype.xml?type_id=105">105</r25:event_type_id> <r25:event_type_name>CABINET</r25:event_type_name> <r25:node_type>C</r25:node_type> <r25:node_type_name>cabinet</r25:node_type_name> <r25:state>1</r25:state> <r25:state_name>Tentative</r25:state_name> <r25:event_locator>2005-AAAAMQ</r25:event_locator> <r25:event_title/> <r25:favorite>F</r25:favorite> <r25:organization_id/> <r25:organization_name/> <r25:parent_id/> <r25:cabinet_id xl:href="event.xml?event_id=328">328</r25:cabinet_id> <r25:cabinet_name>cabinet 09/2005-08/2006</r25:cabinet_name> <r25:start_date>2005-09-01</r25:start_date> <r25:end_date>2006-08-31</r25:end_date> <r25:registration_url/> <r25:last_mod_dt>2008-02-27T14:22:43-05:00</r25:last_mod_dt> <r25:last_mod_user>abc00296004</r25:last_mod_user> </r25:event> </r25:events> And here is what I'm using for code - I'll trying to throw these into a bunch of arrays where I can format the output however I want: <?php $ch = curl_init(); curl_setopt($ch, CURLOPT_URL, "http://somedomain.com/blah.xml"); curl_setopt ($ch, CURLOPT_HTTPHEADER, Array("Content-Type: text/xml")); curl_setopt($ch, CURLOPT_USERPWD, "username:password"); curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1); $output = curl_exec($ch); curl_close($ch); $xml = new SimpleXmlElement($output); foreach ($xml->events->event as $entry){ $dc = $entry->children('http://www.collegenet.com/r25'); echo $entry->event_name . "<br />"; echo $entry->event_id . "<br /><br />"; }

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  • Inventory count in CakePHP

    - by metrobalderas
    We are developing an inventory tracking system. Basically we've got an order table in which orders are placed. When an order is payed, the status changes from 0 to 1. This table has multiple children in another table order_items. This is the main structure. CREATE TABLE order( id INT UNSIGNED AUTO_INCREMENT PRIMARY KEY, user_id INT UNSIGNED, status INT(1), total INT UNSIGNED ); CREATE TABLE order_items( id INT UNSIGNED AUTO_INCREMENT PRIMARY KEY, order_id INT UNSIGNED, article_id INT UNSIGNED, size enum('s', 'm', 'l', 'xl'), quantity INT UNSIGNED ); Now, we've got a stocks table with similar architecture for the acquisitions. This is the structure. CREATE TABLE stock( id INT UNSIGNED AUTO_INCREMENT PRIMARY KEY, article_id INT UNSIGNED ); CREATE TABLE stock_items( id INT UNSIGNED AUTO_INCREMENT PRIMARY KEY, stock_id INT UNSIGNED, size enum('s', 'm', 'l', 'xl'), quantity INT(2) ); The main difference is that stocks has no status field. What we are looking for is a way to sum each article size from stock_items, then sum each article size from order_items where Order.status = 1 and substract both these items to find our current inventory. This is the table we want to get from a single query: Size | Stocks | Sales | Available s | 10 | 3 | 7 m | 15 | 13 | 2 l | 7 | 4 | 3 Initially we thought abouth using complex find conditions, but perhaps that's the wrong approach. Also, since it's not a direct join, it turns out to be quite hard. This is the code we have to retrieve the stock's total for each item. function stocks_total($id){ $find = $this->StockItem->find('all', array( 'conditions' => array( 'StockItem.stock_id' => $this->find('list', array('conditions' => array('Stock.article_id' => $id))) ), 'fields' => array_merge( array( 'SUM(StockItem.cantidad) as total' ), array_keys($this->StockItem->_schema) ), 'group' => 'StockItem.size', 'order' => 'FIELD(StockItem.size, \'s\', \'m\' ,\'l\' ,\'xl\') ASC' )); return $find; } Thanks.

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  • The blogs I turn upto&hellip;

    - by DAXShekhar
    I turn around the pages of Following blogs  Satya Srikant (who is also my brother ;)) http://geekswithblogs.net/ssmantha/Default.aspx   Kamal http://kamalblogs.wordpress.com   Prabhat Samuel http://geekswithblogs.net/Prabhats/Default.aspx   Vanya Kashperuk http://kashperuk.blogspot.com/ Mfp’s two cents http://blogs.msdn.com/mfp/   ……. more to add to list … ;)

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  • Book Review: SSIS Design Patterns

    - by andyleonard
    Samuel Vanga ( Blog | @SamuelVanga ) has posted a review of our new book SSIS Design Patterns at his blog . Several of Sam’s statements struck me, but none more than this: Within a few hours of reading SQL Server 2012 Integration Services Design Patterns , it stood out that none of the authors were trying to impress by showing what they all know in SSIS. Instead, they focused on describing solutions and patterns in a great detail (exactly why I paid for). Sam mentions he could not locate the source...(read more)

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  • Does "Ubuntu for Android" (12.04) work with the Samsung Galaxy S2?

    - by Charles Hadeed
    I'm trying to buy a new Android phone and I own an Ubuntu 12.04 computer... I have the choice of a Google Galaxy Nexus, Samsung Galaxy S2, and a HTC Sensation XL. I am aware that the HTC already works with it but i would prefer to buy the samsung. I already have the phone hardware specifications and have checked but i am not sure with the samsung or the nexus. So which of these phones work for Ubuntu 12.04's 'Ubuntu for Android' feature?

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  • send variable fancybox onclick event

    - by samuel saul
    hi, i want to send href value. but its not working. function display () { $.fancybox({ 'href': 'index.php', 'width' : '75%', 'height' : '75%', 'autoScale' : false, 'transitionIn' : 'none', 'transitionOut' : 'none', 'type' : 'iframe' }); } i tryed this : function display (who) { $.fancybox({ 'href': 'index.php'+who, 'width' : '75%', 'height' : '75%', 'autoScale' : false, 'transitionIn' : 'none', 'transitionOut' : 'none', 'type' : 'iframe' }); } <a onclick="javascript:display("?id=11");" href="#" >create</a> this onclick event inside the innerhtml so its not working with '' why

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  • Mercurial extensions not working in Windows 7 x64?

    - by Samuel Meacham
    We are test driving Mercurial at work. We don't want to have to enter our user/pass each time we interact with a repository, so we set up the mercurial_keyring extension. We: Installed Python 2.6.5 (32 or 64 bit, depending on the system) Installed setuptools (for easy_install.exe) easy_install keyring easy_install mercurial_keyring And then made the appropriate changes to %userprofile%/mercurial.ini in the [auth] section. It works fine on my colleague's computer (32bit xp sp3), but it does not work on my machine (Windows 7 Ultimate x64). Also noteworthy, the setuptools had to be built from source on Win 7 x64 (python setup.py bdist_wininst, then run the resulting setuptools-0.6c11.win-amd64.exe). Using just hg.exe from the Mercurial 1.5 binary installation (the .msi), I get this error when I run hg.exe: * failed to import extension mercurial_keyring: No module named mercurial_keyring I tried to change my mercurial.ini, to specify the path to the mercurial_keyring.py file, instead of having mercurial find it (since it's in the PYTHONPATH). Old: [extensions] mercurial_keyring = New: [extensions] mercurial_keyring = c:/mercurial/extensions/mercurial_keyring.py The error changes to: abort: could not import module keyring! So while providing the path to the mercurial_keyring extension works, the dependent keyring module still cannot be found. After further investigation, it appears that NO extensions work. They all produce the error: * failed to import extension [extension name]: No module named [module name] It appears that when running hg.exe, it is not aware of PYTHONPATH. I have tried: Python 2.6.5 32 bit Python 2.6.5 64 bit Building Mercurial 1.5 from source with MinGW Building Mercurial 1.5 from source with MSVC9 Using hg.exe from the 1.5 binary dist (.msi) Using the hg.py in c:\python26\scripts when building from source Various configurations in %userprofile%/mercurial.ini Using setuptools (easy_install.exe) to install keyring and mercurial_keyring Building keyring and mercurial_keyring from source (python setup.py bdist_wininst) Nothing works. The closest I've got is using hg.py when building from source. It at least doesn't give me errors, and actually creates %userprofile%/wincrypto_pass.cfg when I enter my credentials. But on subsequent requests, it doesn't enter the credentials automatically. It prompts me for them again. Interestingly, TortoiseHG is using the keyring. I just can't get it to work on the command line. I think something is going on with Win 7 x64 that is preventing mercurial (hg.exe) from seeing the PYTHONPATH, so it can't find any of the installed modules. Does anyone have extensions working in Win 7 x64? Specifically with the binary installation of mercurial (not hg.py)?

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  • Webkit iPhone App : How to dynamically change the user zoom (or scale, pich & zoom) in the viewport

    - by Samuel Michelot
    I use JQTouch for an iPhone app. JQtouch disable by default the possibility to pinch&zoom the page. For one page (containing a big image), i need to enable the pinch & zoom feature. This is easy : var viewport = $("head meta[name=viewport]"); viewport.attr('content', 'width=320, initial-scale=1, maximum-scale=10.0, minimum-scale=1, user-scalable=1'); But after user has play with the pinch & zoom, I need to dynamically reset the zoom (scale) to the default. I tried to reset the viewport: viewport.attr('content', 'width=320, initial-scale=1.0, maximum-scale=1.0, user-scalable=0;'); After calling the above code, it's not possible to zoom anymore (because of user-scalable=0;), but it doesn't change the current scale to the default. I am looking for something like setScale(1), or to change an attribute like current-scale=1 Any idea ?

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  • Java enums: Gathering info from another enums

    - by Samuel Carrijo
    I made a similar question a few days ago, but now I have new requirements, and new challenges =). As usual, I'm using the animal enums for didactic purposes, once I don't want to explain domain-specific stuff I have a basic enum of animals, which is used by the whole zoo (I can add stuff to it, but must keep compatibility): public enum Animal { DOG, ELEPHANT, WHALE, SHRIMP, BIRD, GIRAFFE; } I need to categorize them in a few, non-related categories, like gray animals (whale (my whale is gray) and elephant), small animals (bird, shrimp and dog), sea animals (whale and shrimp). I could, as suggested in my previous questions, add a lot of booleans, like isGray, isSmall and isFromSea, but I'd like an approach where I could keep this somewhere else (so my enum doesn't need to know much). Something like: public enum Animal { DOG, ELEPHANT, WHALE, SHRIMP, BIRD, GIRAFFE; public boolean isGray() { // What comes here? } } Somewhere else public enum GrayAnimal { WHALE, ELEPHANT; } How is this possible? Am I requesting too much from Java?

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  • naming conventions for buttons in user interface

    - by Samuel
    User interface for web applications in general contain various buttons for performing CRUD operations. What would be the suggested naming convention for button labels while performing the following actions.. User creation (Add User... or Add User or Add user) Event creation (Add Event... or Add Event or Add event) View users button (List All Users or List All users or List all users ) Most of the sites seem to contain the last option (e.g. Add user) where the first alphabet in the word is capitalized and rest all are lower case). What would be a better practice here?

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  • glassfish v3.0 hangs no app is ever deployed and no error is ever shown

    - by Samuel Lopez
    I have a web app that uses JSF 2.0 with richFaces and primeFaces, hibernate and java and I use NetBeans 7.1.2 as the IDE when I run the app the glassfish server is started and the log shows this: Launching GlassFish on Felix platform Información: Running GlassFish Version: GlassFish Server Open Source Edition 3.1.2 (build 23) Información: Grizzly Framework 1.9.46 started in: 20ms - bound to [0.0.0.0:4848] Información: Grizzly Framework 1.9.46 started in: 32ms - bound to [0.0.0.0:8181] Información: Grizzly Framework 1.9.46 started in: 59ms - bound to [0.0.0.0:8080] Información: Grizzly Framework 1.9.46 started in: 32ms - bound to [0.0.0.0:3700] Información: Grizzly Framework 1.9.46 started in: 21ms - bound to [0.0.0.0:7676] Información: Registered org.glassfish.ha.store.adapter.cache.ShoalBackingStoreProxy for persistence-type = replicated in BackingStoreFactoryRegistry Información: SEC1002: Security Manager is OFF. Información: SEC1010: Entering Security Startup Service Información: SEC1143: Loading policy provider com.sun.enterprise.security.provider.PolicyWrapper. Información: SEC1115: Realm [admin-realm] of classtype [com.sun.enterprise.security.auth.realm.file.FileRealm] successfully created. Información: SEC1115: Realm [file] of classtype [com.sun.enterprise.security.auth.realm.file.FileRealm] successfully created. Información: SEC1115: Realm [certificate] of classtype [com.sun.enterprise.security.auth.realm.certificate.CertificateRealm] successfully created. Información: SEC1011: Security Service(s) Started Successfully Información: WEB0169: Created HTTP listener [http-listener-1] on host/port [0.0.0.0:8080] Información: WEB0169: Created HTTP listener [http-listener-2] on host/port [0.0.0.0:8181] Información: WEB0169: Created HTTP listener [admin-listener] on host/port [0.0.0.0:4848] Información: WEB0171: Created virtual server [server] Información: WEB0171: Created virtual server [__asadmin] Información: WEB0172: Virtual server [server] loaded default web module [] Información: Inicializando Mojarra 2.1.6 (SNAPSHOT 20111206) para el contexto '/test' Información: Hibernate Validator 4.2.0.Final Información: WEB0671: Loading application [test] at [/test] Información: CORE10010: Loading application test done in 4,885 ms Información: GlassFish Server Open Source Edition 3.1.2 (23) startup time : Felix (1,848ms), startup services(5,600ms), total(7,448ms) Información: JMX005: JMXStartupService had Started JMXConnector on JMXService URL service:jmx:rmi://SJ007:8686/jndi/rmi://SJ007:8686/jmxrmi Información: WEB0169: Created HTTP listener [http-listener-1] on host/port [0.0.0.0:8080] Información: Grizzly Framework 1.9.46 started in: 14ms - bound to [0.0.0.0:8080] Información: WEB0169: Created HTTP listener [http-listener-2] on host/port [0.0.0.0:8181] Información: Grizzly Framework 1.9.46 started in: 12ms - bound to [0.0.0.0:8181] but right there it hangs and the deploy bar keeps running but no more actions are shown, nothing else is logged either it just stays there until I stop the deploy Is there any other error log to debug glassfish server? Any thoughts? I have re installed glassfish and NetBeans but it all seems the same. I think this started happening after I had to force-restart my computer with NetBeans stil open and the app deployed, but it's hard to know for sure if this was the real catalyst. Any thoughts or help is appreciated thanks. Is it an app error? if so why no errors in the log are shown?

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  • Javascript Certification

    - by Livingston Samuel
    Is there any proper Certification for Javascript, that covers all the advanced topics of Javascript including the DOM (Document Object Model), BOM (Browser Object Model) and CSS Object Model, that can really evaluate the skills? I've no idea how to scale myself on my JS skills, so any suggestions would be beneficial.

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  • Python readability hints for a Java programmer

    - by Samuel Carrijo
    I'm a java programmer, but now entering the "realm of python" for some stuff for which Python works better. I'm quite sure a good portion of my code would look weird for a Python programmer (e.g. using parenthesis on every if). I know each language has its own conventions and set of "habits". So, from a readability standpoint what are conventions and practices which is "the way to go" in Java, but are not really the "pythonic way" to do stuff?

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  • How to secure a WCF service using NetNamedPipesBinding so that it can only be called by the current

    - by Samuel Jack
    I'm using a WCF service with the NetNamedPipesBinding to communicate between two AppDomains in my process. How do I secure the service so that it is not accessible to other users on the same machine? I have already taken the precaution of using a GUID in the Endpoint Address, so there's a little security through obscurity, but I'm looking for a way of locking the service down using ACL or something similar.

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  • Why can't c# use inline anonymous lambdas or delegates?

    - by Samuel Meacham
    I hope I worded the title of my question appropriately. In c# I can use lambdas (as delegates), or the older delegate syntax to do this: Func<string> fnHello = () => "hello"; Console.WriteLine(fnHello()); Func<string> fnHello2 = delegate() { return "hello 2"; }; Console.WriteLine(fnHello2()); So why can't I "inline" the lambda or the delegate body, and avoid capturing it in a named variable (making it anonymous)? // Inline anonymous lambda not allowed Console.WriteLine( (() => "hello inline lambda")() ); // Inline anonymous delegate not allowed Console.WriteLine( (delegate() { return "hello inline delegate"; })() ); An example that works in javascript (just for comparison) is: alert( (function(){ return "hello inline anonymous function from javascript"; })() ); Which produces the expected alert box. UPDATE: It seems you can have an inline anonymous lambda in C#, if you cast appropriately, but the amount of ()'s starts to make it unruly. // Inline anonymous lambda with appropriate cast IS allowed Console.WriteLine( ((Func<string>)(() => "hello inline anonymous lambda"))() ); Perhaps the compiler can't infer the sig of the anonymous delegate to know which Console.WriteLine() you're trying to call? Does anyone know why this specific cast is required?

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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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