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  • Comparison operators not supported for type IList when Paging data in Linq to Sql

    - by Dan
    I can understand what the error is saying - it can't compare a list. Not a problem, other than the fact that I don't know how to not have it compare a list when I want to page through a model with a list as a property. My Model: Event : IEvent int Id string Title // Other stuff.. LazyList<EventDate> Dates // The "problem" property Method which pages the data (truncated): public JsonResult JsonEventList(int skip, int take) { var query = _eventService.GetEvents(); // Do some filtering, then page data.. query = query.Skip(skip).Take(take); return Json(query.ToArray()); } As I said, the above is truncated quite a bit, leaving only the main point of the function: filter, page and return JSON'd data. The exception occurs when I enumerate (.ToArray()). The Event object is really only used to list the common objects of all the event types (Meetings, Birthdays, etc - for example). It still implements IEvent like the other types, so I can't just remove the LazyList<EventDate> Dates' property unless I no longer implementIEvent` Anyway, is there a way to avoid this? I don't really want to compare a LazyList when I page, but I do not know how to resolve this issue. Thank you in advance! :)

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  • Why does Hibernate 2nd level cache only cache queries within a session?

    - by Synesso
    Using a named query in our application and with ehcache as the provider, it seems that the query results are tied to the session within the cache. Any attempt to access the value from the cache for a second time results in a LazyInitializationException We have set lazy = true for the following mapping because this object is also used by another part of the system which does not require the reference... and we want to keep it lean. <class name="domain.ReferenceAdPoint" table="ad_point" mutable="false" lazy="false"> <cache usage="read-only"/> <id name="code" type="long" column="ad_point_id"> <generator class="assigned" /> </id> <property name="name" column="ad_point_description" type="string"/> <set name="synonyms" table="ad_point_synonym" cascade="all-delete-orphan" lazy="true"> <cache usage="read-only"/> <key column="ad_point_id" /> <element type="string" column="synonym_description" /> </set> </class> <query name="find.adpoints.by.heading">from ReferenceAdPoint adpoint left outer join fetch adpoint.synonyms where adpoint.adPointField.headingCode = ?</query> Here's a snippet from our hibernate.cfg.xml <property name="hibernate.cache.provider_class">net.sf.ehcache.hibernate.SingletonEhCacheProvider</property> <property name="hibernate.cache.use_query_cache">true</property> It doesn't seem to make sense that the cache would be constrained to the session. Why are the cached queries not usable outside of the (relatively short-lived) sessions?

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  • set map in google maps with TimerTask

    - by Chad White
    I would like to change the Position of the map in google maps v2 But Ive done it in a TimerTask ... target, zoom, bearing and so on and it says "IllegalStateException - not on the main thread What should I do? Any help? class Task extends TimerTask { @Override public void run() { CameraPosition cameraPosition = new CameraPosition.Builder() .target(Zt) // Sets the center of the map to Mountain View .zoom(12) // Sets the zoom .bearing(180) // Sets the orientation of the camera to east .tilt(30) // Sets the tilt of the camera to 30 degrees .build(); // Creates a CameraPosition from the builder mMap.moveCamera(CameraUpdateFactory.newCameraPosition(cameraPosition)); } } Timer timer = new Timer(); timer.scheduleAtFixedRate(new Task(), 0, 20000);

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  • Calculate the contentsize of scrollview

    - by neha
    Hi all, I'm having a scrollview as the detailedview of tableview cell. There are multiple views on the detailedview like labels, buttons etc. which I'm creating through interface builder. What I'm creating through interface builder is static. I'm putting everything on a view of height 480. A label on my detailedview is having dynamic text which can extend to any length. The problem is that I need to set the scrollview's content size for which I need its height. How shall I set scrollview's height provided the content is dynamic?

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  • Output on namespaced xpath

    - by user347928
    Hi there, I have the following code and have had some trouble with a specific field and it's output. The namespace is connected but doesn't seem to be outputting on the required field. Any info on this would be great. import org.w3c.dom.Document; import org.xml.sax.SAXException; import javax.xml.parsers.DocumentBuilderFactory; import javax.xml.parsers.DocumentBuilder; import javax.xml.parsers.ParserConfigurationException; import javax.xml.xpath.XPathFactory; import javax.xml.xpath.XPath; import javax.xml.xpath.XPathExpressionException; import java.io.ByteArrayInputStream; import java.io.IOException; public class test { public static void main(String args[]) { String xmlStr = "<aws:UrlInfoResponse xmlns:aws=\"http://alexa.amazonaws.com/doc/2005-10-05/\">\n" + " <aws:Response xmlns:aws=\"http://awis.amazonaws.com/doc/2005-07-11\">\n" + " <aws:OperationRequest>\n" + " <aws:RequestId>blah</aws:RequestId>\n" + " </aws:OperationRequest>\n" + " <aws:UrlInfoResult>\n" + " <aws:Alexa>\n" + " <aws:TrafficData>\n" + " <aws:DataUrl type=\"canonical\">harvard.edu/</aws:DataUrl>\n" + " <aws:Rank>1635</aws:Rank>\n" + " </aws:TrafficData>\n" + " </aws:Alexa>\n" + " </aws:UrlInfoResult>\n" + " <aws:ResponseStatus xmlns:aws=\"http://alexa.amazonaws.com/doc/2005-10-05/\">\n" + " <aws:StatusCode>Success</aws:StatusCode>\n" + " </aws:ResponseStatus>\n" + " </aws:Response>\n" + "</aws:UrlInfoResponse>"; DocumentBuilderFactory xmlFact = DocumentBuilderFactory.newInstance(); xmlFact.setNamespaceAware(true); DocumentBuilder builder = null; try { builder = xmlFact.newDocumentBuilder(); } catch (ParserConfigurationException e) { e.printStackTrace(); } Document doc = null; try { doc = builder.parse( new ByteArrayInputStream( xmlStr.getBytes())); } catch (SAXException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } System.out.println(doc.getDocumentElement().getNamespaceURI()); System.out.println(xmlFact.isNamespaceAware()); String xpathStr = "//aws:OperationRequest"; XPathFactory xpathFact = XPathFactory.newInstance(); XPath xpath = xpathFact.newXPath(); String result = null; try { result = xpath.evaluate(xpathStr, doc); } catch (XPathExpressionException e) { e.printStackTrace(); //To change body of catch statement use File | Settings | File Templates. } System.out.println("XPath result is \"" + result + "\""); } } Thanks Tony

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  • WF -- how do I use a custom activity without creating it in a separate Workflow Activity Library?

    - by Kevin Craft
    I am trying to accomplish something that seems like it should be very simple. I have a State Machine Workflow Console Application with a workflow in it. I have created a custom activity for it. This activity will NEVER be used ANYWHERE ELSE. I just want to use this activity on my workflow, but: It does not appear in the toolbox. I cannot drag it from the Solution Explorer onto the workflow designer. I absolutely do not want to create a separate State Machine Workflow Activity Library, since that will just clutter my solution. Like I said, I will never use this activity in any other project, so I would like to keep it confined to this one...but I just can't figure out how to get it onto the designer! Am I going crazy!? Here is the code for the activity: public partial class GameSearchActivity: Activity { public GameSearchActivity() { InitializeComponent(); } public static DependencyProperty QueryProperty = System.Workflow.ComponentModel.DependencyProperty.Register("Query", typeof(string), typeof(GameSearchActivity)); [Description("Query")] [Category("Dependency Properties")] [Browsable(true)] [DesignerSerializationVisibility(DesignerSerializationVisibility.Visible)] public string Query { get { return ((string)(base.GetValue(GameSearchActivity.QueryProperty))); } set { base.SetValue(GameSearchActivity.QueryProperty, value); } } public static DependencyProperty ResultsProperty = System.Workflow.ComponentModel.DependencyProperty.Register("Results", typeof(string), typeof(GameSearchActivity)); [Description("Results")] [Category("Dependency Properties")] [Browsable(true)] [DesignerSerializationVisibility(DesignerSerializationVisibility.Visible)] public IEnumerable<Game_GamePlatform> Results { get { return ((IEnumerable<Game_GamePlatform>)(base.GetValue(GameSearchActivity.ResultsProperty))); } set { base.SetValue(GameSearchActivity.ResultsProperty, value); } } protected override ActivityExecutionStatus Execute(ActivityExecutionContext executionContext) { IDataService ds = executionContext.GetService<IDataService>(); Results = ds.SearchGames(Query); return ActivityExecutionStatus.Closed; } } Thanks. EDIT: OK, so I've discovered that if I change the project type from Console Application to Class Library, the custom activity appears in the toolbox. However, this is not acceptable. It needs to be a Console/Windows Application. Anyone know a way around this?

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  • I have a problem with mysql and php

    - by neo skosana
    Hi I have a problem, this is my code: $db = new mysqli("localhost", "root", "", "blah"); $result1 = $db-query("select * from c_register where email = '$eml' and password = '$pass'"); if($result1-fetch_array()) { $auth->createSession(); $_SESSION['user'] = 'client'; promptUser("You have successfully logged in!!!","index.php"); } $db = new mysqli("localhost", "root", "", "blah"); $result2 = $db-query("select * from b_register where email = '$eml' and password = '$pass'"); if($result2-fetch_array()) { $auth->createSession(); $_SESSION['user'] = 'business'; promptUser("You have successfully logged in!!!","index.php"); } $db = new mysqli("localhost", "root", "", "blah"); $result3 = $db-query("select * from g_register where email = '$eml' and password = '$pass'"); if($result3-fetch_array()) { $auth->createSession(); $_SESSION['user'] = 'employee'; promptUser("You have successfully logged in!!!","index.php"); } $db = new mysqli("localhost", "root", "", "blah"); $result4 = $db-query("select * from k_register where email = '$eml' and password = '$pass'"); if($result4-fetch_array()) { $auth->createSession(); $_SESSION['user'] = 'super'; promptUser("You have successfully logged in!!!","index.php"); } else { promptUser("Username/Password do not match. Please try again!!!",""); } Funny enough this code works, but I no that I went about it the wrong way. I am new with php and mysql, so please help. I also tried e.gresult4->free(); for all the variable that save the data, and I got this error: Fatal error: Call to a member function free() on a non-object in...

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  • Why for only some actions must I call setTarget?

    - by Max Pierce
    For most actions, I just click and drag in InterfaceBuilder to "wire up" a call from some interface object to my code. For example, if I want to know when the user single-clicks a row in a table, I drag a connection from the table's action to my controller's action. But now let's consider the user double-clicking a row. If I want one of my actions to be called when this happens, I need to call not only -[NSTableView setDoubleAction] but also -[NSControl setTarget]. Why? To be clear, I am not asking why Interface Builder doesn't support setDoubleAction. All tools have limitations. I am trying to gain a greater understanding about how and why setTarget doesn't seem to be necessary unless and until I want setDoubleAction to work. Another way to ask this question would be: Why don't I need to do anything in Interface Builder to set the target of the table's (single-click) action?

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  • Add CSS to Form Type is Symfony2

    - by Umair Iqbal
    I have an edit form, The form is made through symfony2 Form types. I checked the documentation but couldn't find any option for adding CSS to the form. The form display the data correctly and everything is fine what I want to do is to add styling to each field. My Edit Type is public function buildForm(FormBuilder $builder, array $options) { $builder ->add('id', 'hidden') ->add('patent_name', 'text', array('label' => 'Patent Name')) ->add('description', 'textarea', array('label' => 'Description', 'required' => false)) ->add('appln_auth','text', array('label' => 'Application Authorization')) ; } Anyone has any idea ho I can add css ? Thanks

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  • Accidentally deletion of classes from XCode 3.2.5

    - by Alok Srivastava
    Accidentally my classes folder is deleted with reference from xcode(project). i try to recover them from trash but it was not present in trash. how ever i used svn for backup. but after check out the whole project when i try to run the project then it gives ann error 2012-06-05 09:46:59.651 Lisnx[527:207] Unknown class LisnxAppDelegate in Interface Builder file. 2012-06-05 09:46:59.652 Lisnx[527:207] Unknown class LisnxViewController in Interface Builder file. 2012-06-05 09:46:59.656 Lisnx[527:207] * Terminating app due to uncaught exception 'NSUnknownKeyException', reason: '[ setValue:forUndefinedKey:]: this class is not key value coding-compliant for the key viewController.'

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  • Getting the last User ID in Zend Framework

    - by Ryan Murphy
    Using MySQL query browser, I manually made a table called users and input some date in the fields. I set the primary key to id and set it to auto increment. There are 3 rows, the highest id is 3. I then made the following class in the method directory to call upon the data in the table etc. class Application_Model_DbTable_User extends Zend_Db_Table_Abstract { protected $_name = 'user'; public function getLatestUserId() { $id = $this->getAdapter()->lastInsertId(); return $id; } } In the controller I do the following which gets the value generated by the method and lets the view access it: $usersDbModel = new Application_Model_DbTable_User(); $lastUserId = $usersDbModel->getLatestUserId(); $this->view->lastUserId = $lastUserId; In the view I then echo it to display it to the user: echo $this->lastUserId; However, even though my last id in the users table is 3. It displays 0. I have also tried: public function getLatestUserId() { $sql = 'SELECT max(id) FROM user'; $query = $this->query($sql); $result = $query->fetchAll(); return $result; } But this just throws out a server error. What have I done wrong? Am I missing something? Is there another way of doing this?

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  • Java document parsing over internet using POST

    - by Travis
    I've looked all around and decided to make my own library for accessing the EVE API. Requests are sent to a server address such as /account/Characters.xml.aspx. Characters.xml.aspx requires two item be submitted in POST and then it returns an XML file. So far I have this but it does not work, probably becuase I am using GET instead of POST: //Get the API data DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance(); DocumentBuilder builder = factory.newDocumentBuilder(); String url = "http://api.eveonline.com/account/Characters.xml.aspx?userID="+ userID+"?apiKey="+key; Document doc = builder.parse(url); How would I go about being able to parst an XML file that is generated by submitting variables in POST?

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  • which toString() method can be used performance wise??

    - by Mrityunjay
    hi, I am working on one project for performance enhancement. I had one doubt, while we are during a process, we tend to trace the current state of the DTO and entity used. So, for this we have included toString() method in all POJOs for the same. I have now implemented toString() in three different ways which are following :- public String toString() { return "POJO :" + this.class.getName() + " RollNo :" + this.rollNo + " Name :" + this.name; } public String toString() { StringBuffer buff = new StringBuffer("POJO :").append(this.class.getName()).append(" RollNo :").append(this.rollNo).append(" Name :").append(this.name); return buff.toString(); } public String toString() { StringBuilder builder = new StringBuilder("POJO :").append(this.class.getName()).append(" RollNo :").append(this.rollNo).append(" Name :").append(this.name); return builder .toString(); } can anyone please help me to find out which one is best and should be used for enhancing performance.

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  • Mysql for update

    - by shantanuo
    MySQL supports "for update" keyword. Here is how I tested that it is working as expected. I opened 2 browser tabs and executed the following commands in one window. mysql> start transaction; Query OK, 0 rows affected (0.00 sec) mysql> select * from myxml where id = 2 for update; .... mysql> update myxml set id = 3 where id = 2 limit 1; Query OK, 1 row affected, 1 warning (0.00 sec) Rows matched: 1 Changed: 1 Warnings: 0 mysql> commit; Query OK, 0 rows affected (0.08 sec) In another window, I started the transaction and tried to take an update lock on the same record. mysql> start transaction; Query OK, 0 rows affected (0.00 sec) mysql> select * from myxml where id = 2 for update; Empty set (43.81 sec) As you can see from the above example, I could not select the record for 43 seconds as the transaction was being processed by another application in the Window No 1. Once the transaction was over, I got to select the record, but since the id 2 was changed to id 3 by the transaction that was executed first, no record was returned. My question is what are the disadvantages of using "for update" syntax? If I do not commit the transaction that is running in window 1 will the record be locked for-ever?

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  • Is it possible to find out what FlashBuilder is doing during compilation?

    - by justkevin
    I've found that Flash Builder 4 (formerly Flex Builder) has trouble working with large projects. After a certain point, builds seem to take longer and longer. I've tried many different ways of improving build time including: Moving embedded resources into externally linked projects. Using -incremental. Tweaking the .ini jvm settings including memory and -server. Turning off automatic build (I'd prefer not to have to do this, because one of the main reasons for using an IDE is to be told about errors as you make them). Deleting the project and re-checking out from the repository. While some of these may help a bit, the performance is still annoyingly slow. I feel if I knew what was taking so long I could refactor my projects to build faster. Is there some setting that tells FlashBuilder to let me see what parts of the build process take so much time?

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  • Merge computed data from two tables back into one of them

    - by Tyler McHenry
    I have the following situation (as a reduced example). Two tables, Measures1 and Measures2, each of which store an ID, a Weight in grams, and optionally a Volume in fluid onces. (In reality, Measures1 has a good deal of other data that is irrelevant here) Contents of Measures1: +----+----------+--------+ | ID | Weight | Volume | +----+----------+--------+ | 1 | 100.0000 | NULL | | 2 | 200.0000 | NULL | | 3 | 150.0000 | NULL | | 4 | 325.0000 | NULL | +----+----------+--------+ Contents of Measures2: +----+----------+----------+ | ID | Weight | Volume | +----+----------+----------+ | 1 | 75.0000 | 10.0000 | | 2 | 400.0000 | 64.0000 | | 3 | 100.0000 | 22.0000 | | 4 | 500.0000 | 100.0000 | +----+----------+----------+ These tables describe equivalent weights and volumes of a substance. E.g. 10 fluid ounces of substance 1 weighs 75 grams. The IDs are related: ID 1 in Measures1 is the same substance as ID 1 in Measures2. What I want to do is fill in the NULL volumes in Measures1 using the information in Measures2, but keeping the weights from Measures1 (then, ultimately, I can drop the Measures2 table, as it will be redundant). For the sake of simplicity, assume that all volumes in Measures1 are NULL and all volumes in Measures2 are not. I can compute the volumes I want to fill in with the following query: SELECT Measures1.ID, Measures1.Weight, (Measures2.Volume * (Measures1.Weight / Measures2.Weight)) AS DesiredVolume FROM Measures1 JOIN Measures2 ON Measures1.ID = Measures2.ID; Producing: +----+----------+-----------------+ | ID | Weight | DesiredVolume | +----+----------+-----------------+ | 4 | 325.0000 | 65.000000000000 | | 3 | 150.0000 | 33.000000000000 | | 2 | 200.0000 | 32.000000000000 | | 1 | 100.0000 | 13.333333333333 | +----+----------+-----------------+ But I am at a loss for how to actually insert these computed values into the Measures1 table. Preferably, I would like to be able to do it with a single query, rather than writing a script or stored procedure that iterates through every ID in Measures1. But even then I am worried that this might not be possible because the MySQL documentation says that you can't use a table in an UPDATE query and a SELECT subquery at the same time, and I think any solution would need to do that. I know that one workaround might be to create a new table with the results of the above query (also selecting all of the other non-Volume fields in Measures1) and then drop both tables and replace Measures1 with the newly-created table, but I was wondering if there was any better way to do it that I am missing.

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  • Need help tuning a SQL statement

    - by jeffself
    I've got a table that has two fields (custno and custno2) that need to be searched from a query. I didn't design this table, so don't scream at me. :-) I need to find all records where either the custno or custno2 matches the value returned from a query on the same table based on a titleno. In other words, the user types in 1234 for the titleno. My query searches the table to find the custno associated with the titleno. It also looks for the custno2 for that titleno. Then it needs to do a search on the same table for all other records that have either the custno or custno2 returned in the previous search in the custno or custno2 fields for those other records. Here is what I've come up with: SELECT BILLYR, BILLNO, TITLENO, VINID, TAXPAID, DUEDATE, DATEPIF, PROPDESC FROM TRCDBA.BILLSPAID WHERE CUSTNO IN (select custno from trcdba.billspaid where titleno = '1234' union select custno2 from trcdba.billspaid where titleno = '1234' and custno2 != '') OR CUSTNO2 IN (select custno from trcdba.billspaid where titleno = '1234' union select custno2 from trcdba.billspaid where titleno = '1234' and custno2 != '') The query takes about 5-10 seconds to return data. Can it be rewritten to work faster?

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  • OO model for nsxmlparser when delegate is not self

    - by richard
    Hi, I am struggling with the correct design for the delegates of nsxmlparser. In order to build my table of Foos, I need to make two types of webservice calls; one for the whole table and one for each row. It's essentially a master-query then detail-query, except the master-query-result-xml doesn't return enough information so i then need to query the detail for each row. I'm not dealing with enormous amounts of data. Anyway - previously I've just used NSXMLParser *parser = [[NSXMLParser alloc]init]; [parser setDelegate:self]; [parser parse]; and implemented all the appropriate delegate methods in whatever class i'm in. In attempt at cleanliness, I've now created two separate delegate classes and done something like: NSXMLParser *xp = [[NSXMLParser alloc]init]; MyMasterXMLParserDelegate *masterParserDelegate = [[MyMasterXMLParser]alloc]init]; [xp setDelegate:masterParserDelegate]; [xp parse]; In addition to being cleaner (in my opinion, at least), it also means each of the -parser:didStartElement implementations don't spend most of the time trying to figure out which xml they're parsing. So now the real crux of the problem. Before i split out the delegates, i had in the main class that was also implementing the delegate methods, a class-level NSMutableArray that I would just put my objects-created-from-xml in when -parser:didEndElement found the 'end' of each record. Now the delegates are in separate classes, I can't figure out how to have the -parser:didEndElement in the 'detail' delegate class "return" the created object to the calling class. At least, not in a clean OO way. I'm sure i could do it with all sorts of nasty class methods. Does the question make sense? Thanks.

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  • Setting Up a Wordpress Function in theme's function.php File

    - by user1609391
    I am trying to create the below function in my theme's function.php file and call it from my taxonomy.php file via query_brands_geo('dealers', 'publish', '1', $taxtype, $geo, $brands); all variables are set in taxonomy.php. The below query works perfect if I put it directly in my taxonomy.php file. What am I missing to make this work as a function? As a function I get this error statement for argument repeated for 2-6: Warning: Missing argument 2 for query_brands_geo() function query_brands_geo($posttype, $poststatus, $paidvalue, $taxtype, $geo, $brands) { /* Custom Query for a brand/geo combination to display dealers with a certain brand and geography */ //Query only for brands/geography combo and paid dealers $wp_query = new WP_Query(); $args = array( 'post_type' => '$posttype', 'post_status' => array($poststatus), 'orderby' => 'rand', 'posts_per_page' => 30, 'meta_query' => array( array( 'key' => 'wpcf-paid', 'value' => array($paidvalue), 'compare' => 'IN', ) ), 'tax_query' => array( 'relation' => 'AND', array( 'taxonomy' => $taxtype, 'field' => 'slug', 'terms' => $geo ), array( 'taxonomy' => 'brands', 'field' => 'slug', 'terms' => $brands ) ) ); $wp_query->query($args); } add_action( 'after_setup_theme', 'query_brands_geo' );

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  • LINQ Joins - Performance

    - by Meiscooldude
    I am curious on how exactly LINQ (not LINQ to SQL) is performing is joins behind the scenes in relation to how Sql Server performs joins. Sql Server before executing a query, generates an Execution Plan. The Execution Plan is basically an Expression Tree on what it believes is the best way to execute the query. Each node provides information on whether to do a Sort, Scan, Select, Join, ect. On a 'Join' node in our execution plan, we can see three possible algorithms; Hash Join, Merge Join, and Nested Loops Join. Sql Server will choose which algorithm to for each Join operation based on expected number of rows in Inner and Outer tables, what type of join we are doing (some algorithms don't support all types of joins), whether we need data ordered, and probably many other factors. Join Algorithms: Nested Loop Join: Best for small inputs, can be optimized with ordered inner table. Merge Join: Best for medium to large inputs sorted inputs, or an output that needs to be ordered. Hash Join: Best for medium to large inputs, can be parallelized to scale linearly. LINQ Query: DataTable firstTable, secondTable; ... var rows = from firstRow in firstTable.AsEnumerable () join secondRow in secondTable.AsEnumerable () on firstRow.Field<object> (randomObject.Property) equals secondRow.Field<object> (randomObject.Property) select new {firstRow, secondRow}; SQL Query: SELECT * FROM firstTable fT INNER JOIN secondTable sT ON fT.Property = sT.Property Sql Server might use a Nested Loop Join if it knows there are a small number of rows from each table, a merge join if it knows one of the tables has an index, and Hash join if it knows there are a lot of rows on either table and neither has an index. Does Linq choose its algorithm for joins? or does it always use one?

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  • Hibernate: fetching multiple bags efficiently

    - by Jens Jansson
    Hi! I'm developing a multilingual application. For this reason many objects have in their name and description fields collections of something I call LocalizedStrings instead of plain strings. Every LocalizedString is basically a pair of a locale and a string localized to that locale. Let's take an example an entity, let's say a book -object. public class Book{ @OneToMany private List<LocalizedString> names; @OneToMany private List<LocalizedString> description; //and so on... } When a user asks for a list of books, it does a query to get all the books, fetches the name and description of every book in the locale the user has selected to run the app in, and displays it back to the user. This works but it is a major performance issue. For the moment hibernate makes one query to fetch all the books, and after that it goes through every single object and asks hibernate for the localized strings for that specific object, resulting in a "n+1 select problem". Fetching a list of 50 entities produces about 6000 rows of sql commands in my server log. I tried making the collections eager but that lead me to the "cannot simultaneously fetch multiple bags"-issue. Then I tried setting the fetch strategy on the collections to subselect, hoping that it would do one query for all books, and after that do one query that fetches all LocalizedStrings for all the books. Subselects didn't work in this case how i would have hoped and it basically just did exactly the same as my first case. I'm starting to run out of ideas on how to optimize this. So in short, what fetching strategy alternatives are there when you are fetching a collection and every element in that collection has one or multiple collections in itself, which has to be fetch simultaneously.

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  • Amazon Product API ResponseGroups and Default results

    - by aboxy
    A. In our application, most of the data we work with is stored as free text .i.e. there is no categorization done as of now. We are using openNLP libraries to make sense of the data(extract keywords/classify) and do a query to Amazon web services to pull the results of the query. We use searchindex=All and keywords=. Results are not always returned and we basically get 'AWS.ECommerceService.NoExactMatches' How to avoid that? 1) Is there a way to specify default results if no match found? e.g. Amazon carousel widget does that if the search query did not return results, it basically show some computer items. 2) Should I batch the request always and add another search criteria to every request? If my first criteria does not pull any results, we can be sure that our 2nd query will always pull results(possibly caching?) Here is one search criteria 'Open Circle Hoop Earrings Polished Stainless Steel Open Circle Hoop Earrings Polished Stainless Steel DiamondShark' This return no results via API. On Amazon site,I get alternative suggestions with some results which are pretty relevant. Is there a way to pull those results? B. We just need a thumbnail image and a title and description for our app. Which responseGroup is appropriate? We are using medium rt now but there is awful lot of information even with that responseGroup. Any help is appreciated. thanks

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  • Passing a outside variable into a <asp:sqldatasource> tag. ASP.NET 2.0

    - by MadMAxJr
    I'm designing some VB based ASP.NET 2.0, and I am trying to make more use of the various ASP tags that visual studio provides, rather than hand writing everything in the code-behind. I want to pass in an outside variable from the Session to identify who the user is for the query. <asp:sqldatasource id="DataStores" runat="server" connectionstring="<%$ ConnectionStrings:MY_CONNECTION %>" providername="<%$ ConnectionStrings:MY_CONNECTION.ProviderName %>" selectcommand="SELECT THING1, THING2 FROM DATA_TABLE WHERE (THING2 IN (SELECT THING2 FROM RELATED_DATA_TABLE WHERE (USERNAME = @user)))" onselecting="Data_Stores_Selecting"> <SelectParameters> <asp:parameter name="user" defaultvalue ="" /> </SelectParameters> </asp:sqldatasource> And on my code behind I have: Protected Sub Data_Stores_Selecting(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.SqlDataSourceSelectingEventArgs) Handles Data_Stores.Selecting e.Command.Parameters("user").Value = Session("userid") End Sub Oracle squaks at me with ORA-01036, illegal variable name. Am I declaring the variable wrong in the query? I thought external variables share the same name with a @ prefixed. from what I understand, this should be placing the value I want into the query when it executes the select. EDIT: Okay, thanks for the advice so far, first error was corrected, I need to use : and not @ for the variable declaration in the query. Now it generates an ORA-01745 invalid host/bind variable name. EDIT AGAIN: Okay, looks like user was a reserved word. It works now! Thanks for other points of view on this one. I hadn't thought of that approach.

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