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  • SQL use DISTINCT with ORDER BY (Oracle)

    - by ArneRie
    Hi, i have an strange problem. I want to select "timestamps" from an DB Table with Distinct and orderded by timestamp. ID TimeStamp -- --------- 1 123456789 2 123456789 3 333333333 4 334345643 In my PHP Script: $sql = "SELECT DISTINCT TIMESTAMP FROM TIMESTAMPS ORDER BY TIMESTAMP" When i use order by, the values are returned twice? Without order by the result is correct.. but not sorted. We are using Oracle 10g Any ideaS?

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  • How can I order fields in Django ModelForm?

    - by joozek
    I have an 'order' Model: class Order(models.Model): date_time=models.DateTimeField() # other stuff And I'm using Django ModelForm class to render a form, but I want to display date and time widgets separately. I've came up with this: class Form(forms.ModelForm): class Meta: model = Order exclude = ('date_time',) date = forms.DateField() time = forms.TimeField() The problem is that I want to put these fields somewhere between 'other stuff'

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  • Execute PHP after new Order in Magento

    - by Israel Lopez
    Hello There, I'm trying to figure out where I could drop in some PHP code to notify a CRM we are using (Solve360) that a new order has been placed, and that an event should be created (API) to fulfill the order. Order Product Checkout Complete Checkout & Capture CC Side notify CRM Done Not sure where to start, but I have had to make some small tweaks to fix the Quantum Gateway payment processor to work. In that module it appears that the objects for the order (email, amt, details) were available. However it seems it would be quite 'dirty' to insert more PHP code in there. Ideas? PHP 5.2.x & Magento 1.4.x

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  • JPA2 + Hibernate + Order By

    - by Jan
    Hi. Is it possible (using Hibernate and JPA2 Criteria Builder [1]) to order by a method's result rather than an entity's member? public class X { protected X() {} public String member; public String getEvaluatedValue() { // order by return "some text " + member; } } What I want to achive is order by the result of getEvaluatedValue(). Is that possible? Thanks in advanced. [1] http://docs.jboss.org/hibernate/entitymanager/3.5/reference/en/html_single/#querycriteria

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  • Select rows in random order and then reverse it

    - by Faruz
    I need to select rows in random order and return a query which holds the rows in both regular order and in reverse order. This is done to simulate a fantasy draft for a basketball game I'm working on. For example, I need a result set as followed: team1 1 team2 2 team6 3 team9 4 team9 5 team6 6 team2 7 team1 8 As you can see, the first four teams are random then then following four are in reverse order. Hope I managed to explain the problem, if not - please comment and I'll explain further.

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  • Adding new column in Sales Order View Items in Magento Admin

    - by fdierre
    In the admin interface of Magento I need to modify the tables in the Sales / Order / View order so that it shows, besides the products name, their manufacturer as well. I'm trying to look for the file to modify to make that happen. I thought I would find a section with all the columns that are displayed in app/code/core/Mage/Sales/Block/Order/Item/Renderer/Default.php but by inspecting it there seem to be no reference to the columns/product attributes. I also tried to modify app/design/adminhtml/default/default/template/sales/order/view/items/renderer/default.phtml by changing <?php echo $this->getColumnHtml($_item, 'name') ?> into <?php echo $this->getColumnHtml($_item, 'manufacturer') ?> but it changed nothing, so I suppose that file is not involved... Can anybody please point me to the right file to modify? Thank you!

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  • Drupal: tags order in back-end edit-content pages

    - by Patrick
    hi, can I order alphabetically the tags in my edit content pages ? See screenshot here: http://dl.dropbox.com/u/72686/tagsOrder.png Currently the order is given by the Taxonomy Manager module (I installed in my Drupal). I would like to know if I should use jQuery to order the tags in my back-end pages. thanks

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  • Alternatives to sign() in sqlite for custom order by

    - by Pentium10
    I have a string column which contains some numeric fields, but a lot are 0, empty string or null. The rest are numbers having different range, all positive. I tried to create a custom order by. The order would be done by two fields. First I would like to order the fields that have this number 0 and then sort by name. So something this would work: select * from table order by sign(referenceid) desc, name asc; But Sqlite lacks the sign() -1/0/1 function, and I am on Android and I can't create user defined functions. What other options I have to get this sort done.

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  • Rails Active Record find(:all, :order => ) issue.

    - by CodingWithoutComments
    I seem to be unable to use :order_by for more than one column at a time. For example, I have a "Show" model with date and attending columns. If I run the following code: @shows = Show.find(:all, :order => "date") I get the following results: [#<Show id: 7, date: "2009-04-18", attending: 2>, #<Show id: 1, date: "2009-04-18", attending: 78>, #<Show id: 2, date: "2009-04-19", attending: 91>, #<Show id: 3, date: "2009-04-20", attending: 16>, #<Show id: 4, date: "2009-04-21", attending: 136>] If I run the following code: @shows = Show.find(:all, :order => "attending DESC") [#<Show id: 4, date: "2009-04-21", attending: 136>, #<Show id: 2, date: "2009-04-19", attending: 91>, #<Show id: 1, date: "2009-04-18", attending: 78>, #<Show id: 3, date: "2009-04-20", attending: 16>, #<Show id: 7, date: "2009-04-18", attending: 2>] But, if I run: @shows = Show.find(:all, :order => "date, attending DESC") OR @shows = Show.find(:all, :order => "date, attending ASC") OR @shows = Show.find(:all, :order => "date ASC, attending DESC") I get the same results as only sorting by date: [#<Show id: 7, date: "2009-04-18", attending: 2>, #<Show id: 1, date: "2009-04-18", attending: 78>, #<Show id: 2, date: "2009-04-19", attending: 91>, #<Show id: 3, date: "2009-04-20", attending: 16>, #<Show id: 4, date: "2009-04-21", attending: 136>] Where as, I want to get these results: [#<Show id: 1, date: "2009-04-18", attending: 78>, #<Show id: 7, date: "2009-04-18", attending: 2>, #<Show id: 2, date: "2009-04-19", attending: 91>, #<Show id: 3, date: "2009-04-20", attending: 16>, #<Show id: 4, date: "2009-04-21", attending: 136>] This is the query being generated from the logs: [4;35;1mUser Load (0.6ms)[0m [0mSELECT * FROM "users" WHERE ("users"."id" = 1) LIMIT 1[0m [4;36;1mShow Load (3.0ms)[0m [0;1mSELECT * FROM "shows" ORDER BY date ASC, attending DESC[0m [4;35;1mUser Load (0.6ms)[0m [0mSELECT * FROM "users" WHERE ("users"."id" = 1) [0m Finally, here is my model: create_table "shows", :force => true do |t| t.string "headliner" t.string "openers" t.string "venue" t.date "date" t.text "description" t.datetime "created_at" t.datetime "updated_at" t.decimal "price" t.time "showtime" t.integer "attending", :default => 0 t.string "time" end What am I missing? What am I doing wrong? UPDATE: Thanks for all your help, but it seems that all of you were stumped as much as I was. What solved the problem was actually switching databases. I switched from the default sqlite3 to mysql.

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  • css not:first-child selector

    - by OTARIKI
    I have div tag and him is several ul tags. If I trying set css properties only for first ul tag, this code works: div ul:first-child { background-color: #900; } But when i want set css properties each ul tags, except first, I trying this: div ul:not:first-child { background-color: #900; } also this div ul:not(:first-child) { background-color: #900; } and this div ul:first-child:after { background-color: #900; } But effect none. Someone tell please, how must write in css: "each element, except first" ?

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  • How to output items in Order in MySQL?

    - by RailsRor
    I have a column called "menu_order" which has no default value. When I select the contents of this column using the following select statement: SELECT * FROM categories ORDER BY menu_order ASC It lists the category items that have nothing as their menu order first and then the one's that have 1's and 2's and 3's. Is there any way to prevent SQL from take nothing to come before numbers when I am trying to list things in order? So for example, if I have: cat_name | menu_order ---------------------- Lunch | 1 Dinner | And I perform my query, the output should be: Lunch Dinner Not: Dinner Lunch

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  • Union and order by

    - by David Lively
    Consider a table like tbl_ranks -------------------------------- family_id | item_id | view_count -------------------------------- 1 10 101 1 11 112 1 13 109 2 21 101 2 22 112 2 23 109 3 30 101 3 31 112 3 33 109 4 40 101 4 51 112 4 63 109 5 80 101 5 81 112 5 88 109 I need to generate a result set with the top two(2) rows for a subset of family ids (say, 1,2,3 and 4) ordered by view count. I'd like to do something like select top 2 * from tbl_ranks where family_id = 1 order by view_count union all select top 2 * from tbl_ranks where family_id = 2 order by view_count union all select top 2 * from tbl_ranks where family_id = 3 order by view_count union all select top 2 * from tbl_ranks where family_id = 4 order by view_count but, of course, order by isn't valid in a union all context in this manner. Any suggestions? I know I could run a set of 4 queries, store the results into a temp table and select the contents of that temp as the final result, but I'd rather avoid using a temp table if possible. Note: in the real app, the number of records per family id is indeterminate, and the view_counts are also not fixed as they appear in the above example.

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  • sortable list using jquery ui not passing updated list order

    - by Matthew Berman
    I am following the sortable lists railscast and got everything working except when I sort, the same (original) order gets passed to the update method each time, so it doesn't update the true order. Here's the code: In the view: %tbody#lineup{"data-update-url" => sort_lineups_url} - @lineup.pieces.each_with_index do |piece, index| = content_tag_for :tr, piece do = render 'piece', :piece => piece, :index => index and pieces.js.coffee: jQuery -> $('#lineup').sortable( axis: 'y' update: -> $.post($(this).data('update-url'), $(this).sortable('serialize')) ); sort and show methods of lineupscontroller: def show @lineup = Lineup.find_by_user_id(current_user.id) @pieces = @lineup.pieces.order("position") end def sort params[:piece].each_with_index do |id, index| current_user.lineup.pieces.update_all({position: index+1}, {id: id}) end render nothing: true end and the update request: Started POST "/lineups/sort" for 127.0.0.1 at 2012-06-24 20:06:14 -0700 Processing by LineupsController#sort as */* Parameters: {"piece"=>["8", "2", "1", "4", "3", "7"]} User Load (0.4ms) SELECT `users`.* FROM `users` WHERE `users`.`id` = 2 LIMIT 1 Lineup Load (0.6ms) SELECT `lineups`.* FROM `lineups` WHERE `lineups`.`user_id` = 2 LIMIT 1 SQL (2.9ms) UPDATE `pieces` INNER JOIN `piece_lineups` ON `pieces`.`id` = `piece_lineups`.`piece_id` SET `position` = 1 WHERE `piece_lineups`.`lineup_id` = 3 AND `pieces`.`id` = 8 SQL (0.6ms) UPDATE `pieces` INNER JOIN `piece_lineups` ON `pieces`.`id` = `piece_lineups`.`piece_id` SET `position` = 2 WHERE `piece_lineups`.`lineup_id` = 3 AND `pieces`.`id` = 2 SQL (0.6ms) UPDATE `pieces` INNER JOIN `piece_lineups` ON `pieces`.`id` = `piece_lineups`.`piece_id` SET `position` = 3 WHERE `piece_lineups`.`lineup_id` = 3 AND `pieces`.`id` = 1 SQL (0.5ms) UPDATE `pieces` INNER JOIN `piece_lineups` ON `pieces`.`id` = `piece_lineups`.`piece_id` SET `position` = 4 WHERE `piece_lineups`.`lineup_id` = 3 AND `pieces`.`id` = 4 SQL (0.6ms) UPDATE `pieces` INNER JOIN `piece_lineups` ON `pieces`.`id` = `piece_lineups`.`piece_id` SET `position` = 5 WHERE `piece_lineups`.`lineup_id` = 3 AND `pieces`.`id` = 3 SQL (0.5ms) UPDATE `pieces` INNER JOIN `piece_lineups` ON `pieces`.`id` = `piece_lineups`.`piece_id` SET `position` = 6 WHERE `piece_lineups`.`lineup_id` = 3 AND `pieces`.`id` = 7 Rendered text template (0.0ms) so each time i drag+drop the list, it sends the same order again. what am I doing wrong that the params isn't passing the right, updated order? Completed 200 OK in 2757ms (Views: 1.0ms | ActiveRecord: 6.7ms)

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  • how to order string logically

    - by just_name
    Q: I have the following case : set of letters (grades) A,A+,A-,B,B+,B- stored as strings in the database i wanna to order these grades logically from the small one to the big one ,, but this not what happen in real.. because these are strings the order is: A,A+,A- i wanna ASC A-,A,A+ DESC A+,A,A- i bind those grades in drop down list and i wanna these grades with this logical order in it.. is there any idea how to do something like this..

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  • Hibernate 1:M relationship ,row order, constant values table and concurrency

    - by EugeneP
    table A and B need to have 1:M relationship a and b are added during application runtime, so A created, then say 4 B's created. Each B instance has to come in order, so that I could later extract them in the same order as I added them. The app will be a web-app running on Tomcat, so 10 instances may work simultaneously. So my question are: 1) How to preserve inserting order, so that I could extract B instances that A references in the same order as I persisted them. That's tricky, because we add to a Collection and then it gets saved (am I right?). So, it depends on how Hibernate saves it, what if it changes the order in what we added instances? I've seen something like LIST instead of SET when describing relationships, is that what I need? 2) How to add a 3-rd column to B so that I could differentiate the instances, something like SEX(M,F,U) in B table. Do I need a special table, or there's and easy way to describe constants in Hibernate. What do you recommend? 3) Talking about concurrency, what methods do you recommend to use? There should be no collisions in the db and as you see, there might easily be some if rows are not inserted (PK added) right where it is invoked without delays ?

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  • Order mysql results without identifier

    - by Alex Crooks
    Usually I would have a table field called ID on auto increment. That way I could order using this field etc. However I have no control over the structure of a table, and wondered how to get the results in reverse order to default. I'm currently using $q = mysql_query("SELECT * FROM ServerChat LIMIT 15"); However like I said there is no field I can order on, so is there a way to tell mysql to reverse the order it gets the results? I.e last row to first row instead of the default.

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  • [SQL] Select 3 lastest order for each customer

    - by Ratiug
    Hi Here is my table CusOrder that collect customer order OrderID Cus_ID Product_ID NumberOrder OrderDate 1 0000000001 9 1 6/5/2553 0:00:00 2 0000000001 10 1 6/5/2553 0:00:00 3 0000000004 9 2 13/4/2553 0:00:00 4 0000000004 9 1 17/3/2553 0:00:00 5 0000000002 9 1 22/1/2553 0:00:00 7 0000000005 9 1 16/12/2552 0:00:00 8 0000000003 9 3 13/12/2552 0:00:00 10 0000000001 9 2 19/11/2552 0:00:00 11 0000000003 9 2 10/11/2552 0:00:00 12 0000000002 9 1 23/11/2552 0:00:00 I need to select 3 lastest order for each customer and I need all customer so it will show each customer and his/her 3 lastest order how can I do it sorry for my bad english

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  • This Week in Geek History: NORAD Tracks Santa, First HTTP Test, Babbage’s Birthday

    - by Jason Fitzpatrick
    History trivia shouldn’t be limited to just treaty dates and wars ending, we’re marking off major milestones in geek history—one week at at time. This week in history we’ve got Santa on the Cold War radar, baby HTTP going for a spin, and Babbage’s birth to help usher in the age of computers. Latest Features How-To Geek ETC How to Use the Avira Rescue CD to Clean Your Infected PC The Complete List of iPad Tips, Tricks, and Tutorials Is Your Desktop Printer More Expensive Than Printing Services? 20 OS X Keyboard Shortcuts You Might Not Know HTG Explains: Which Linux File System Should You Choose? HTG Explains: Why Does Photo Paper Improve Print Quality? An Alternate Star Wars Christmas Special [Video] Sunset in a Tropical Paradise Wallpaper Natural Wood Grain Icons for Your Desktop and App Launcher Docks My Blackberry Is Not Working! The Apple Too?! [Funny Video] Hidden Tracks Your Stolen Mac; Free Until End of January Why the Other Checkout Line Always Moves Faster

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  • First time using Java Web Start in Ubuntu - Fatal Launch Exception

    - by MountainX
    I've been using Ubuntu for a while and Java Web Start applications have never "just worked" in the current or any prior version, so I ignored them until now. However, now I have a need to get them working in Firefox. When I am on a page like this: http://www.oracle.com/technetwork/java/demos-nojavascript-137100.html I want to be able to click on the demos as suggested and have them run. I'm running Ubuntu 11.10 with Gnome 3 and/or Linux Mint 12 (64 bit) with OpenJDK 6, OpenJDK 7 and Sun Java 6. My default is currently: /usr/lib/jvm/java-6-openjdk/jre/bin/java $ whereis javaws javaws: /usr/bin/javaws /etc/alternatives/javaws - /usr/lib/jvm/java-6-openjdk/jre/bin/javaws Here's the error I get when I try to run a Java Web Start application: net.sourceforge.jnlp.LaunchException: Fatal: Initialization Error: Could not initialize application. at net.sourceforge.jnlp.Launcher.createApplication(Launcher.java:776) at net.sourceforge.jnlp.Launcher.launchApplication(Launcher.java:552) at net.sourceforge.jnlp.Launcher$TgThread.run(Launcher.java:887) Caused by: net.sourceforge.jnlp.LaunchException: Fatal: Initialization Error: A fatal error occurred while trying to verify jars. at net.sourceforge.jnlp.runtime.JNLPClassLoader.initializeResources(JNLPClassLoader.java:448) at net.sourceforge.jnlp.runtime.JNLPClassLoader.<init>(JNLPClassLoader.java:176) at net.sourceforge.jnlp.runtime.JNLPClassLoader.getInstance(JNLPClassLoader.java:295) at net.sourceforge.jnlp.Launcher.createApplication(Launcher.java:767) ... 2 more Caused by: net.sourceforge.jnlp.LaunchException: Fatal: Initialization Error: A fatal error occurred while trying to verify jars. at net.sourceforge.jnlp.runtime.JNLPClassLoader.initializeResources(JNLPClassLoader.java:448) at net.sourceforge.jnlp.runtime.JNLPClassLoader.<init>(JNLPClassLoader.java:176) at net.sourceforge.jnlp.runtime.JNLPClassLoader.getInstance(JNLPClassLoader.java:295) at net.sourceforge.jnlp.Launcher.createApplication(Launcher.java:767) at net.sourceforge.jnlp.Launcher.launchApplication(Launcher.java:552) at net.sourceforge.jnlp.Launcher$TgThread.run(Launcher.java:887) Here's another example: http://docs.oracle.com/javase/tutorial/uiswing/events/keylistener.html net.sourceforge.jnlp.LaunchException: Fatal: Read Error: Could not read or parse the JNLP file. at net.sourceforge.jnlp.Launcher.fromUrl(Launcher.java:491) at net.sourceforge.jnlp.Launcher.launch(Launcher.java:283) at net.sourceforge.jnlp.runtime.Boot.run(Boot.java:199) at net.sourceforge.jnlp.runtime.Boot.run(Boot.java:51) at java.security.AccessController.doPrivileged(Native Method) at net.sourceforge.jnlp.runtime.Boot.main(Boot.java:165) Caused by: java.io.IOException: port out of range:-2147483648 at net.sourceforge.jnlp.JNLPFile.openURL(JNLPFile.java:255) at net.sourceforge.jnlp.JNLPFile.<init>(JNLPFile.java:185) at net.sourceforge.jnlp.JNLPFile.<init>(JNLPFile.java:162) at net.sourceforge.jnlp.JNLPFile.<init>(JNLPFile.java:148) at net.sourceforge.jnlp.Launcher.fromUrl(Launcher.java:477) ... 5 more Caused by: java.io.IOException: port out of range:-2147483648 at net.sourceforge.jnlp.JNLPFile.openURL(JNLPFile.java:255) at net.sourceforge.jnlp.JNLPFile.<init>(JNLPFile.java:185) at net.sourceforge.jnlp.JNLPFile.<init>(JNLPFile.java:162) at net.sourceforge.jnlp.JNLPFile.<init>(JNLPFile.java:148) at net.sourceforge.jnlp.Launcher.fromUrl(Launcher.java:477) at net.sourceforge.jnlp.Launcher.launch(Launcher.java:283) at net.sourceforge.jnlp.runtime.Boot.run(Boot.java:199) at net.sourceforge.jnlp.runtime.Boot.run(Boot.java:51) at java.security.AccessController.doPrivileged(Native Method) at net.sourceforge.jnlp.runtime.Boot.main(Boot.java:165)

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  • Security considerations for my first eStore.

    - by RPK
    I have a website through which I am going to sell few products. It is hosted on a simple shared-hosting and does not have SSL. On the products page, each product has a Buy Now button created from my PayPal Merchant account. PayPal recommends to use it's Button Factory to create secure buttons and save it inside PayPal itself. I have followed the same advice and the code of any button is secure and does not disclose any information on either a product or it's price. When the user clicks on a Buy Now button, he/she is taken to PayPal site where a page is opened in SSL for the user to fill in the credit card and shipping details. After a successful transaction, the control is passed back to my site. I want to know whether there is still any chance when security could be compromised.

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  • Getting It Right The First Time

    - by andyleonard
    Introduction This post is the seventeenth part of a ramble-rant about the software business. The current posts in this series are: Goodwill, Negative and Positive Visions, Quests, Missions Right, Wrong, and Style Follow Me Balance, Part 1 Balance, Part 2 Definition of a Great Team The 15-Minute Meeting Metaproblems: Drama The Right Question Software is Organic, Part 1 Metaproblem: Terror I Don't Work On My Car A Turning Point Human Doings Everything Changes This post is about getting software right...(read more)

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  • First impressions of Scala

    - by Scott Weinstein
    I have an idea that it may be possible to predict build success/failure based on commit data. Why Scala? It’s a JVM language, has lots of powerful type features, and it has a linear algebra library which I’ll need later. Project definition and build Neither maven or the scala build tool (sbt) are completely satisfactory. This maven **archetype** (what .Net folks would call a VS project template) mvn archetype:generate `-DarchetypeGroupId=org.scala-tools.archetypes `-DarchetypeArtifactId=scala-archetype-simple `-DremoteRepositories=http://scala-tools.org/repo-releases `-DgroupId=org.SW -DartifactId=BuildBreakPredictor gets you started right away with “hello world” code, unit tests demonstrating a number of different testing approaches, and even a ready made `.gitignore` file - nice! But the Scala version is behind at v2.8, and more seriously, compiling and testing was painfully slow. So much that a rapid edit – test – edit cycle was not practical. So Lab49 colleague Steve Levine tells me that I can either adjust my pom to use fsc – the fast scala compiler, or use sbt. Sbt has some nice features It’s fast – it uses fsc by default It has a continuous mode, so  `> ~test` will compile and run your unit test each time you save a file It’s can consume (and produce) Maven 2 dependencies the build definition file can be much shorter than the equivalent pom (about 1/5 the size, as repos and dependencies can be declared on a single line) And some real limitations Limited support for 3rd party integration – for instance out of the box, TeamCity doesn’t speak sbt, nor does IntelliJ IDEA Steeper learning curve for build steps outside the default Side note: If a language has a fast compiler, why keep the slow compiler around? Even worse, why make it the default? I choose sbt, for the faster development speed it offers. Syntax Scala APIs really like to use punctuation – sometimes this works well, as in the following map1 |+| map2 The `|+|` defines a merge operator which does addition on the `values` of the maps. It’s less useful here: http(baseUrl / url >- parseJson[BuildStatus] sure you can probably guess what `>-` does from the context, but how about `>~` or `>+`? Language features I’m still learning, so not much to say just yet. However case classes are quite usefull, implicits scare me, and type constructors have lots of power. Community A number of projects, such as https://github.com/scalala and https://github.com/scalaz/scalaz are split between github and google code – github for the src, and google code for the docs. Not sure I understand the motivation here.

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  • First toe in the water with Object Databases : DB4O

    - by REA_ANDREW
    I have been wanting to have a play with Object Databases for a while now, and today I have done just that.  One of the obvious choices I had to make was which one to use.  My criteria for choosing one today was simple, I wanted one which I could literally wack in and start using, which means I wanted one which either had a .NET API or was designed/ported to .NET.  My decision was between two being: db4o MongoDb I went for db4o for the single reason that it looked like I could get it running and integrated the quickest.  I am making a Blogging application and front end as a project with which I can test and learn with these object databases.  Another requirement which I thought I would mention is that I also want to be able to use the said database in a shared hosting environment where I cannot install, run and maintain a server instance of said object database.  I can do exactly this with db4o. I have not tried to do this with MongoDb at time of writing.  There are quite a few in the industry now and you read an interesting post about different ones and how they are used with some of the heavy weights in the industry here : http://blog.marcua.net/post/442594842/notes-from-nosql-live-boston-2010 In the example which I am building I am using StructureMap as my IOC.  To inject the object for db4o I went with a Singleton instance scope as I am using a single file and I need this to be available to any thread on in the process as opposed to using the server implementation where I could open and close client connections with the server handling each one respectively.  Again I want to point out that I have chosen to stick with the non server implementation of db4o as I wanted to use this in a shared hosting environment where I cannot have such servers installed and run.     public static class Bootstrapper    {        public static void ConfigureStructureMap()        {            ObjectFactory.Initialize(x => x.AddRegistry(new MyApplicationRegistry()));        }    }    public class MyApplicationRegistry : Registry    {        public const string DB4O_FILENAME = "blog123";        public string DbPath        {            get            {                return Path.Combine(Path.GetDirectoryName(Assembly.GetAssembly(typeof(IBlogRepository)).Location), DB4O_FILENAME);            }        }        public MyApplicationRegistry()        {            For<IObjectContainer>().Singleton().Use(                () => Db4oEmbedded.OpenFile(Db4oEmbedded.NewConfiguration(), DbPath));            Scan(assemblyScanner =>            {                assemblyScanner.TheCallingAssembly();                assemblyScanner.WithDefaultConventions();            });        }    } So my code above is the structure map plumbing which I use for the application.  I am doing this simply as a quick scratch pad to play around with different things so I am simply segregating logical layers with folder structure as opposed to different assemblies.  It will be easy if I want to do this with any segment but for the purposes of example I have literally just wacked everything in the one assembly.  You can see an example file structure I have on the right.  I am planning on testing out a few implementations of the object databases out there so I can program to an interface of IBlogRepository One of the things which I was unsure about was how it performed under a multi threaded environment which it will undoubtedly be used 9 times out of 10, and for the reason that I am using the db context as a singleton, I assumed that the library was of course thread safe but I did not know as I have not read any where in the documentation, again this is probably me not reading things correctly.  In short though I threw together a simple test where I simply iterate to a limit each time kicking a common task off with a thread from a thread pool.  This task simply created and added an random Post and added it to the storage. The execution of the threads I put inside the Setup of the Test and then simply ensure the number of posts committed to the database is equal to the number of iterations I made; here is the code I used to do the multi thread jobs: [TestInitialize] public void Setup() { var sw = new System.Diagnostics.Stopwatch(); sw.Start(); var resetEvent = new ManualResetEvent(false); ThreadPool.SetMaxThreads(20, 20); for (var i = 0; i < MAX_ITERATIONS; i++) { ThreadPool.QueueUserWorkItem(delegate(object state) { var eventToReset = (ManualResetEvent)state; var post = new Post { Author = MockUser, Content = "Mock Content", Title = "Title" }; Repository.Put(post); var counter = Interlocked.Decrement(ref _threadCounter); if (counter == 0) eventToReset.Set(); }, resetEvent); } WaitHandle.WaitAll(new[] { resetEvent }); sw.Stop(); Console.WriteLine("{0:00}.{1:00} seconds", sw.Elapsed.Seconds, sw.Elapsed.Milliseconds); }   I was not doing this to test out the speed performance of db4o but while I was doing this I could not help but put in a StopWatch and see out of sheer interest how fast it would take to insert a number of Posts.  I tested it out in this case with 10000 inserts of a small, simple POCO and it resulted in an average of:  899.36 object inserts / second.  Again this is just  simple crude test which came out of my curiosity at how it performed under many threads when using the non server implementation of db4o. The spec summary of the computer I used is as follows: With regards to the actual Repository implementation itself, it really is quite straight forward and I have to say I am very surprised at how easy it was to integrate and get up and running.  One thing I have noticed in the exposure I have had so far is that the Query returns IList<T> as opposed to IQueryable<T> but again I have not looked into this in depth and this could be there already and if not they have provided everything one needs to make there own repository.  An example of a couple of methods from by db4o implementation of the BlogRepository is below: public class BlogRepository : IBlogRepository { private readonly IObjectContainer _db; public BlogRepository(IObjectContainer db) { _db = db; } public void Put(DomainObject obj) { _db.Store(obj); } public void Delete(DomainObject obj) { _db.Delete(obj); } public Post GetByKey(object key) { return _db.Query<Post>(post => post.Key == key).FirstOrDefault(); } … Anyways I hope to get a few more implementations going of the object databases and literally just get familiarized with them and the concept of no sql databases. Cheers for now, Andrew

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