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  • Is it possible to load an entire SQL Server CE database into RAM?

    - by DanM
    I'm using LinqToSql to query a small SQL Server CE database. I've noticed that any operations involving sub-properties are disappointingly slow. For example, if I have a Customer table that is referenced by an Order table via a foreign key, LinqToSql will automatically create an EntitySet<Order> property. This is a nice convenience, allowing me to do things like Customer.Order.Where(o => o.ProductName = "Stopwatch"), but for some reason, SQL Server CE hangs up pretty bad when I try to do stuff like this. One of my queries, which isn't really that complicated takes 3-4 seconds to complete. I can get the speed up to acceptable, even fast, if I just grab the two tables individually and convert them to List<Customer> and List<Order>, then join then manually with my own query, but this is throwing out a lot of the appeal of LinqToSql. So, I'm wondering if I can somehow get the whole database into RAM and just query that way, then occasionally save it. Is this possible? How? If not, is there anything else I can do to boost the performance? Note: My database in its initial state is about 250K and I don't expect it to grow to more than 1-2Mb. So, loading the data into RAM certainly wouldn't be a problem from a memory point of view.

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  • Dynamic Data Extract Tools

    - by Kevin McGovern
    I've been searching around for a few weeks now for a tool that either is fully built or a direction of something I could build for dynamically extracting data via a web interface. Basically, what I'm looking for is a way to give users a list of all available data objects from our database and then let them pick ones from the list they'd like to view and set parameters then export the results to an excel file. Right now we're doing it purely with SQL statements but we have hundreds of objects so as you might imagine, those statements are really complex and prone to errors. It would be great if there was a tool available to do this or if someone had an idea of an easy way to organize this. Any help would be greatly appreciated. We've looked at BI tools like QlikView and Tableau but that is probably overkill for what we're trying to do. The open-source BI tools we've looked at seemed really primitive in their functionality. The other thing we looked at was MSAS (our DB is SQL Server) but I'd prefer something that was more database-agnostic and lived on a web server instead of on the database.

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  • WPF Binding Path=/ not working?

    - by Mark
    I've set up my DataContext like this: <Window.DataContext> <c:DownloadManager /> </Window.DataContext> Where DownloadManager is Enumerable<DownloadItem>. Then I set my DataGrid like this: <DataGrid Name="dataGrid1" ItemsSource="{Binding Path=/}" ... So that it should list all the DownloadItems, right? So I should be able to set my columns like: <DataGridTextColumn Binding="{Binding Path=Uri, Mode=OneWay}" Where Uri is a property of the DownloadItem. But it doesn't seem to like this. In the visual property editor, it doesn't recognize Uri is a valid property, so I'm guessing I'm doing something wrong. It was working before, when I had the data grid binding to Values, but then I took that enumerable out of the DownloadManager and made itself enumerable. How do I fix this? PS: By "doesn't work" I mean it doesn't list any items. I've added some to the constructor of the DM, so it shouldn't be empty.

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  • SQL return ORDER BY result as an array

    - by EarthMind
    Is it possible to return groups as an associative array? I'd like to know if a pure SQL solution is possible. Note that I release that I could be making things more complex unnecessarily but this is mainly to give me an idea of the power of SQL. My problem: I have a list of words in the database that should be sorted alphabetically and grouped into separate groups according to the first letter of the word. For example: ape broom coconut banana apple should be returned as array( 'a' => 'ape', 'apple', 'b' => 'banana', 'broom', 'c' => 'coconut' ) so I can easily created sorted lists by first letter (i.e. clicking "A" only shows words starting with a, "B" with b, etc. This should make it easier for me to load everything in one query and make the sorted list JavaScript based, i.e. without having to reload the page (or use AJAX). Side notes: I'm using PostgreSQL but a solution for MySQL would be fine too so I can try to port it to PostgreSQL. Scripting language is PHP.

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  • HTML+CSS: 'a' width doesn't work

    - by Budda
    I have the following code: CSS part: <style type="text/css"> .menu { width:200px; } .menu ul { list-style-image:none; list-style-type:none; } .menu li { margin:2px; } .menu A { height:25px; width:170px; background:url(./images/button-51.png); padding:2px 5px ; } .menu A:link { height:25px; width:170px; background:url(./images/button-51.png); padding:2px 5px ; } </style> HTML part: Everything work fine, but when I add 'DOCTYPE' element in the beginning of the HTML document: <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> the width of 'a' element is not taken into account. Question 1: Why? Question 2: How to fix that? Thanks a lot!

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  • Using jquery to change checkbox status

    - by Jeff
    Hi everyone! I have a list of items that have checkboxes associated with them, and the items are beneath a list header, which also has a checkbox(for db purposes only) which is actually hidden from view. I need to make it so that if any of the checkboxes beneath the header is checked, then the header checkbox is checked as well. BUT I also need to make it so that if all of the checkboxes are unchecked, then the header one is unchecked...how hard is this going to be? This is how I have it setup now: if($('.childCheckBox').is(":checked")){ $('#parentBox').attr('checked', true); } Now I am thinking that if I were to do something where I add an else if clause: else if($('.proBox2').is(not)(":checked"){ alert("uncheck parent"); } But I don't know the correct syntax for is-not, or isn't, or even if there is anything that will do that. Are there any thoughts out there? I need the box to check if one is selected and uncheck if none are selected. Thanks!!

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  • Automatically use inclusion tags (?) in a template, depending on installed apps

    - by Ludwik Trammer
    The title may be a little confusing, but I don't know how else to call it. I would like to create a Django project with a large set of applications you could arbitrary turn on or off using INSTALLED_APPS option in settings.py (you would obviously also need to edit urls.py and run syncdb). After being turned on an app should be able to automatically: Register it's content in site-wide search. Luckily django-haystack has this built-in, so it's not a problem. Register cron jobs. django-cron does exactly that. Not a problem. Register a widget that should be displayed on the homepage. The homepage should include a list of boxes with widgets form different applications. I thought about inclusion tags, because you can put them anywhere on a page and they control both content and presentation. The problem is I don't know how to automatically get a list of inclusion tags provided by my applications, and display them one by one on a homepage. I need a way to register them somehow, and then display all registered tags.

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  • How to update csv column names with database table header

    - by user1523311
    I am facing this problem some past days and now frustrate because I have to do it. I need to update my CSV file columns name with database table header. My database table fields are different from CSV file. Now the problem is that first I want to update column name of CSV file with database table headers and then import its data with field mapping into database. Please help me I don't know how I can solve this. This is my php code: $file = $_POST['fileName']; $filename = "../files/" . $file; $list = $_POST['str']; $array_imp = implode(',', $list); $array_exp = explode(',', $array_imp); $fp = fopen("../files/" . $file, "w"); $num = count($fp); for ($c = 0; $c < $num; $c++) { if ($fp[c] !== '') { fputcsv($fp, $array_exp); } } fclose($fp);

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  • wx_ref and custom wx_object's

    - by Iogann
    Hi! I am developing MDI application with help of wxErlang. I have a parent frame, implemented as wx_object: -module(main_frame). -export([new/0, init/1, handle_call/3, handle_event/2, terminate/2]). -behaviour(wx_object). .... And I have a child frame, implemented as wx_object too: module(child_frame). -export([new/2, init/1, handle_call/3, handle_event/2, terminate/2]). -export([save/1]). -behaviour(wx_object). % some public API method save(Frame) -> wx_object:call(Frame, save). .... I want to call save/1 for an active child frame from the parent frame. There is my code: ActiveChild = wxMDIParentFrame:getActiveChild(Frame), case wx:is_null(ActiveChild) of false - child_frame:save(ActiveChild); _ - ignore end This code fails because ActiveChild is #wx_ref{} with state=[], but wx_object:call/2 needs #wx_ref{} where state is set to the pid of the process which we call. What is the right method to do this? I thought only to store a list of all created child frames with its pids in the parent frame and search the pid in this list, but this is ugly.

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  • Extract information from a Func<bool, T> or alike lambda

    - by Syska
    I''m trying to build a generic cache layer. ICacheRepository Say I have the following: public class Person { public int PersonId { get; set; } public string Firstname { get; set; } public string Lastname { get; set; } public DateTime Added { get; set; } } And I have something like this: list.Where(x => x.Firstname == "Syska"); Here I want to extract the above information, to see if the query supplied the "PersonId" which it did not, so I dont want to cache it. But lets say I run a query like this: list.Where(x => x.PersonId == 10); Since PersonId is my key ... I want to cache it. with the key like "Person_10" and I later can fetch it from the cache. I know its possible to extract the information with Expression<Func<>> but there seems to be a big overhead of doing this (when running compile and extract the Constant values etc. and a bunch of cache to be sure to parse right) Are there a framework for this? Or some smart/golden way of doing this ?

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  • How do I configure encodings (UTF-8) for code executed by Quartz scheduled Jobs in Spring framework

    - by Martin
    I wonder how to configure Quartz scheduled job threads to reflect proper encoding. Code which otherwise executes fine within Springframework injection loaded webapps (java) will get encoding issues when run in threads scheduled by quartz. Is there anyone who can help me out? All source is compiled using maven2 with source and file encodings configured as UTF-8. In the quartz threads any string will have encoding errors if outside ISO 8859-1 characters: Example config <bean name="jobDetail" class="org.springframework.scheduling.quartz.JobDetailBean"> <property name="jobClass" value="example.ExampleJob" /> </bean> <bean id="jobTrigger" class="org.springframework.scheduling.quartz.SimpleTriggerBean"> <property name="jobDetail" ref="jobDetail" /> <property name="startDelay" value="1000" /> <property name="repeatCount" value="0" /> <property name="repeatInterval" value="1" /> </bean> <bean class="org.springframework.scheduling.quartz.SchedulerFactoryBean"> <property name="triggers"> <list> <ref bean="jobTrigger"/> </list> </property> </bean> Example implementation public class ExampleJob extends QuartzJobBean { private Log log = LogFactory.getLog(ExampleJob.class); protected void executeInternal(JobExecutionContext ctx) throws JobExecutionException { log.info("ÅÄÖ"); log.info(Charset.defaultCharset()); } } Example output 2010-05-20 17:04:38,285 1342 INFO [QuartzScheduler_Worker-9] ExampleJob - vÖvÑvñ 2010-05-20 17:04:38,286 1343 INFO [QuartzScheduler_Worker-9] ExampleJob - UTF-8 The same lines of code executed within spring injected beans referenced by servlets in the web-container will output proper encoding. What is it that make Quartz threads encoding dependent?

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  • Populate CruiseControl email publisher user addresses from file

    - by Unsliced
    Currently my CruiseControl.NET email publisher has its list of users hard-coded in the build config file <publishers> [ ... ] <email from="[email protected]" mailhost="stmp.domain.com" mailport="25" includeDetails="TRUE"> <replyto>[email protected]</replyto> <users> <user name="a.user" group="buildmaster" address="[email protected]"/> <user name="b.user" group="developers" address="[email protected]"/> </users> <groups> <group name="developers"> <notifications> <notificationType>Failed</notificationType> <notificationType>Fixed</notificationType> </notifications> </group> <group name="buildmaster"> <notifications> <notificationType>Always</notificationType> </notifications> </group> </groups> <modifierNotificationTypes> <NotificationType>Failed</NotificationType> <NotificationType>Fixed</NotificationType> </modifierNotificationTypes> </email> </publishers> I'd like to be able to read the list of users from an external file. We have dozens of build files and I'd like to streamline the process of adding new users and removing ones that are no longer interested. Can I do this?

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  • Running an application from an USB device...

    - by Workshop Alex
    I'm working on a proof-of-concept application, containing a WCF service with console host and client, both on a single USB device. On the same device I will also have the client application which will connect to this service. The service uses the entity framework to connect to the database, which in this POC will just return a list of names. If it works, it will be used for a larger project. Creating the client and service was easy and this works well from USB. But getting the service to connect to the database isn't. I've found this site, suggesting that I should modify machine.config but that stops the XCopy deployment. This project cannot change any setting of the PC, so this suggestion is bad. I cannot create a deployment setup either. The whole thing just needs to run from USB disk. So, how do I get it to run? (The service just selects a list of names from the database, which it returns to the client. If this POC works, it will do far more complex things!)

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  • gems, bundle command, and ruby not found in new terminal window

    - by user3579987
    So I installed ruby with rvm, ran a bundle install and installed a bunch of gems, etc. It all works just fine in the original terminal window I did all of this in but I opened up a new terminal window and now I'm getting errors like bundle: command not found and gem command not found. I tried doing a symbolic link for the gem command but then when I do gem list it displays a much shorter list of my local gems and not at all the ones I need for bundle install. Is there something I need to do to configure bash or rvm so that it recognizes that I did indeed install all the gems I have installed? name@crunchbang:~/ug_research_portal$ which gem /home/name/.rvm/rubies/ruby-2.1.1/bin/gem name@crunchbang:~/ug_research_portal$ which ruby /home/name/.rvm/rubies/ruby-2.1.1/bin/ruby And in ~/.bashrc: GEM_HOME="/home/name/.rvm/gems/ruby-2.1.1" GEMGLOBAL_HOME="/home/ name/.rvm/gems/ruby-2.1.1@global" export PATH=$PATH:$GEM_HOME/bin:$GEMGLOBAL_HOME/bin:$HOME/.rvm/bin Edit: Looks like my $PATH is somehow wrong? bash: /home/name/bin:/usr/sbin:/sbin:/usr/local/bin:/usr/bin:/bin:/usr/local/games:/usr/games:/home/name/.rvm/gems/ruby-2.1.1/bin:/home/name/.rvm/gems/ruby-2.1.1@global/bin:/home/name/.rvm/bin/: No such file or directory which is odd since ls for /home/name/.rvm/bin and /home/name/.rvm/gems/ruby-2.1.1@global/bin and /home/name/.rvm/gems/ruby-2.1.1/bin work just fine Psych, I was just doing $PATH instead of echo "$PATH" which was giving me the No such file or directory error. The original problem still stands though.

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  • IE7 Debug Issue - Word Breaks in <li>

    - by JCHASE11
    Hello, I am having a very basic problem in IE7 that I cannot seem to fix. If you look at this page: http://vitaminjdesign.com/IAM/company/ you will notice that the vertical nav (ul id="leftcol") is displaying incorrectly in IE7. Each word appears on its own line. Here is my HTML /. CSS: <ul id="leftcol"> <li><a class="active" href="#">Company Overview</a></li> <li><a href="#">Why Choose Parker?</a></li> <li><a href="#">Testimonials</a></li> <li><a href="#">Financing Promotions</a></li> <li><a href="#">Licensing & Credentials</a></li> </ul> ul#leftcol{float:left; width:185px; position:relative; z-index:10;} ul#leftcol li{float:right; clear:right; margin-bottom:14px; list-style:none; list-style-image:none; text-align:right; line-height:1.3; } ul#leftcol li a{color:#505050; text-decoration:none; font-size:15px; float:right;} ul#leftcol li a.active,ul#leftcol li a:hover{color:#89b060;} Any ideas?

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  • Retrieving friend's likes from the Facebook Graph API

    - by Joe Frank
    Howdy- I have been tooling around with the Facebook Graph API and successfully retrieved back a list of my likes, and a list of my friends (once I authenticated using OAuth). But what I really want to achieve is pulling back my friend's likes. When I try and do that, obviously using the same URL that I use to pull back my own likes but subbing the friend's user id for "me", I don't get anything back, unless they have installed the app as well. Then I get them no problem. To be clear, I can only see the likes of friends who have installed my application. So clearly I am running into a security/rights issue of some sort. I could see where this would be the case; you simply aren't allowed to see your friend's likes unless they have installed the same app. Fair enough, but then how is blekko.com doing it? I even tried using FQL without much luck. I suspect I am missing something totally obvious. Anyone had any luck with this? Maybe with the Javascript API or one of the other access methods? Thanks in advance for any guidance.

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  • C++ STL question related to insert iterators and overloaded operators

    - by rshepherd
    #include <list> #include <set> #include <iterator> #include <algorithm> using namespace std; class MyContainer { public: string value; MyContainer& operator=(const string& s) { this->value = s; return *this; } }; int main() { list<string> strings; strings.push_back("0"); strings.push_back("1"); strings.push_back("2"); set<MyContainer> containers; copy(strings.begin(), strings.end(), inserter(containers, containers.end())); } The preceeding code does not compile. In standard C++ fashion the error output is verbose and difficult to understand. The key part seems to be this... /usr/include/c++/4.4/bits/stl_algobase.h:313: error: no match for ‘operator=’ in ‘__result.std::insert_iterator::operator* [with _Container = std::set, std::allocator ]() = __first.std::_List_iterator::operator* [with _Tp = std::basic_string, std::allocator ]()’ ...which I interpet to mean that the assignment operator needed is not defined. I took a look at the source code for insert_iterator and noted that it has overloaded the assignment operator. The copy algorithm must uses the insert iterators overloaded assignment operator to do its work(?). I guess that because my input iterator is on a container of strings and my output iterator is on a container of MyContainers that the overloaded insert_iterator assignment operator can no longer work. This is my best guess, but I am probably wrong. So, why exactly does this not work and how can I accomplish what I am trying to do?

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  • Unit test approach for generic classes/methods

    - by Greg
    Hi, What's the recommended way to cover off unit testing of generic classes/methods? For example (referring to my example code below). Would it be a case of have 2 or 3 times the tests to cover testing the methods with a few different types of TKey, TNode classes? Or is just one class enough? public class TopologyBase<TKey, TNode, TRelationship> where TNode : NodeBase<TKey>, new() where TRelationship : RelationshipBase<TKey>, new() { // Properties public Dictionary<TKey, NodeBase<TKey>> Nodes { get; private set; } public List<RelationshipBase<TKey>> Relationships { get; private set; } // Constructors protected TopologyBase() { Nodes = new Dictionary<TKey, NodeBase<TKey>>(); Relationships = new List<RelationshipBase<TKey>>(); } // Methods public TNode CreateNode(TKey key) { var node = new TNode {Key = key}; Nodes.Add(node.Key, node); return node; } public void CreateRelationship(NodeBase<TKey> parent, NodeBase<TKey> child) { . . .

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  • howto catch jQuery for multiple links but not all

    - by user247245
    I'm trying to dig into jQuery but would like some feedback on how to do things the best way, I have a list with items, which each contains a hidden div that should show upon click on it's parent, list div:ed item1 with link hidden div div:ed item2 with link hidden div .. My current solution is to trace the calling link by it's id and then reusing that ID for showing the correct hidden one: $(document).ready(function() { //jQ should only trigger on links with id="cmLinkINT" $("a").click(function() { //see if it's a comment request. var s = $(this).attr("id"); if (s.indexOf('cmLink') != -1) { //ok, it was a 'show'-link, get the id.. var j = s.substring(6); //ok, now I have the id i want to show (detailsINT) return false; } }); }); What's not clear to me is the best approach, Should I use id for requesting a or trace the id of the parent div. How to avoid that the code triggers on any link? Class? Thankful for any feedback, regards //t

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  • Firing PropertyChanged event in a complex, nested type in WPF

    - by John
    Hey I have a question about the PropertyChanged vent firing in WPF whne it is used in a complex type. I have a class called DataStore and a list of Departments (an ObservableCollection), and each department again has a list of Products. Properties in the Product class that are changed also affect properties in the Department and DataStore class. How does each Product notify the Department it belongs to, and the DataStore (which is the mother class of all) that one or more of its properties have changed their values? Example: a product has a property NumberSoldToday and is bound. The Department has a property called TotalNumberOfProductsSold: public int TotalNumberOfProductsSold { get { int result = 0; foreach(Product p in this.products) result += p.NumberSoldToday; return result; } } And the data store has a property TotalProductsSold (for all departments): public int TotalProductsSold { get { int result = 0; foreach(Product p in this.deparments) result += p.TotalNumberOfProductsSold; return result; } } If all these properties are bound, and the innermost property changes, it must somehow notify that the value of the other 2 changed as well. How? The only way I can see this happening is to hook up the PropertyChanged event in each class. Th event must also fire when deleting, adding to the collection of products and deparments, respectively. Is there a better, more clever way to do this?

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  • How do I introspect on a SQL Server?

    - by MetaHyperBolic
    I have a server with a vendor application which is heavily database-reliant. I need to make some minor changes to the data in a few tables in the database in an automated fashion. Just INSERTs and UPDATEs, nothing fancy. Vendors being vendors, I can never be quite sure when they change the schema of a database during upgrade. To that end, how do I ask the SQL server, in some scriptable fashion, "Hey, does this table still exist? Yeah, cool, okay, but does it have this column? What's the data type and size on that? Is it nullable? Could you give me a list of tables? In this table, could you give me a list of columns? Any primary keys there?" I do not need to do this for the whole schema, only part of it, just a quick check of the database before I launch into things. We have Microsoft SQL Server 2005 on it currently, but it might easily move to Microsoft SQL Server 2008. I am probably not using the correct terminology when searching. I do know that ORM is not only too much overhead for this sort of thing, but also that I have no chance of pitching it to my coworkers.

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  • MVC Validator.TryValidateObject does not validate custom atrribute, validateAllProperties = true

    - by nealsu
    When calling Validator.TryValidateObject with validateAllProperties = true my custom validation attribute does not get triggered. The ValidationResult does not contain an entry for my erroneous property value. Below is the model, attribute and code used to test this. //Model public class Model { [AmountGreaterThanZero] public int? Amount { get; set; } } //Attribute public sealed class AmountGreaterThanZero: ValidationAttribute { private const string errorMessage = "Amount should be greater than zero."; public AmountGreaterThanZero() : base(errorMessage) { } public override string FormatErrorMessage(string name) { return errorMessage; } protected override ValidationResult IsValid(object value, ValidationContext validationContext) { if (value != null) { if ((int)value <= 0) { var message = FormatErrorMessage(validationContext.DisplayName); return new ValidationResult(message); } } return null; } } //Validation Code var container = new Container(); container.ModelList = new List<Model>() { new Model() { Amount = -5 } }; var validationContext = new ValidationContext(container, null, null); var validationResults = new List<ValidationResult>(); var modelIsValid = Validator.TryValidateObject(container, validationContext, validationResults, true); Note: That the validation works fine and ValidationResult returns with correct error message if I use the TryValidateProperty method.

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  • Centering Divisions Around Zero

    - by Mark
    I'm trying to create something that sort of resembles a histogram. I'm trying to create buckets from an array. Suppose I have a random array doubles between -10 and 10; this is very simplified. I then want to specify a center point, in this case 0 and the number of buckets. If I want 4 buckets the division would be -10 to -5, -5 to 0, 0 to 5 and 5 to 10. Not that complicated right. Now if I change the min and max to -12 and -9 and as for 4 divisions its more complicated. I either want a division at -3 and 3; it is centered around 0 ; or one at -6 to 0 and 0 to 6. Its not that hard to find the division size = Math.Ceiling((Abs(Max) + Abs(Min)) / Divisions) Then you would basically have an if statement to determine whether you want it centered on 0 or on an edge. You then iterate out from either 0 or DivisionSize/2 depending on the situation. You may not ALWAYS end up with the specified number of divisions but it will be close. Then you iterate through the array and increment the bin count. Does this seem like a good way to go about this? This method would surely work but it does not seem to be the most elegant. I'm curious as to whether the creation of the bins and the counting from the list could be done in a clever class with linq in a more elegant way? Something like creating the bins and then having each bin be a property {get;} that returns list.Count(x=> x >= Lower && x < Upper).

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  • Stable/repeatable random sort (MySQL, Rails)

    - by Matt Rogish
    I'd like to paginate through a randomly sorted list of ActiveRecord models (rows from MySQL database). However, this randomization needs to persist on a per-session basis, so that other people that visit the website also receive a random, paginate-able list of records. Let's say there are enough entities (tens of thousands) that storing the randomly sorted ID values in either the session or a cookie is too large, so I must temporarily persist it in some other way (MySQL, file, etc.). Initially I thought I could create a function based on the session ID and the page ID (returning the object IDs for that page) however since the object ID values in MySQL are not sequential (there are gaps), that seemed to fall apart as I was poking at it. The nice thing is that it would require no/minimal storage but the downsides are that it is likely pretty complex to implement and probably CPU intensive. My feeling is I should create an intersection table, something like: random_sorts( sort_id, created_at, user_id NULL if guest) random_sort_items( sort_id, item_id, position ) And then simply store the 'sort_id' in the session. Then, I can paginate the random_sorts WHERE sort_id = n ORDER BY position LIMIT... as usual. Of course, I'd have to put some sort of a reaper in there to remove them after some period of inactivity (based on random_sorts.created_at). Unfortunately, I'd have to invalidate the sort as new objects were created (and/or old objects being removed, although deletion is very rare). And, as load increases the size/performance of this table (even properly indexed) drops. It seems like this ought to be a solved problem but I can't find any rails plugins that do this... Any ideas? Thanks!!

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  • Is it possible to cache all the data in a SQL Server CE database using LinqToSql?

    - by DanM
    I'm using LinqToSql to query a small, simple SQL Server CE database. I've noticed that any operations involving sub-properties are disappointingly slow. For example, if I have a Customer table that is referenced by an Order table, LinqToSql will automatically create an EntitySet<Order> property. This is a nice convenience, allowing me to do things like Customer.Order.Where(o => o.ProductName = "Stopwatch"), but for some reason, SQL Server CE hangs up pretty bad when I try to do stuff like this. One of my queries, which isn't really that complicated takes 3-4 seconds to complete. I can get the speed up to acceptable, even fast, if I just grab the two tables individually and convert them to List<Customer> and List<Order>, then join then manually with my own query, but this is throwing out a lot of what makes LinqToSql so appealing. So, I'm wondering if I can somehow get the whole database into RAM and just query that way, then occasionally save it. Is this possible? How? If not, is there anything else I can do to boost the performance besides resorting to doing all the joins manually? Note: My database in its initial state is about 250K and I don't expect it to grow to more than 1-2Mb. So, loading the data into RAM certainly wouldn't be a problem from a memory point of view. Update Here are the table definitions for the example I used in my question: create table Order ( Id int identity(1, 1) primary key, ProductName ntext null ) create table Customer ( Id int identity(1, 1) primary key, OrderId int null references Order (Id) )

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