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  • Hibernate does not allow an embedded object with an int field to be null?

    - by Jason Novak
    Hibernate does not allow me to persist an object that contains an null embedded object with an integer field. For example, if I have a class called Thing that looks like this @Entity public class Thing { @Id public String id; public Part part; } where Part is an embeddable class that looks like this @Embeddable public class Part { public String a; public int b; } then trying to persist a Thing object with a null Part causes Hibernate to throw an Exception. In particular, this code Thing th = new Thing(); th.id = "thing.1"; th.part = null; session.saveOrUpdate(th); causes Hibernate to throw this Exception org.hibernate.PropertyValueException: not-null property references a null or transient value: com.ace.moab.api.jobs.Thing.part My guess is that this is happening because Part is an embedded class and so Part.a and Part.b are simply columns in the Thing database table. Since the Thing.part is null Hibernate wants to set the Part.a and Part.b column values to null for the row for thing.1. However, Part.b is an integer and Hibernate will not allow integer columns in the database to be null. This is what causes the Exception, right? So I am looking for workarounds for this problem. I noticed making Part.b an Integer instead of an int seems to work, but for reasons I won't bore you with this is not a good option for us. Thanks!

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  • Validations for a has_many/belongs_to relationship

    - by Craig Walker
    I have a Recipe model which has_many Ingredients (which in turn belongs_to Recipe). I want Ingredient to be existent dependent on Recipe; an Ingredient should never exist without a Recipe. I'm trying to enforce the presence of a valid Recipe ID in the Ingredient. I've been doing this with a validates :recipe, :presence => true (Rails 3) statement in Ingredient. This works fine if I save the Recipe before adding an Ingredient to it's ingredients collection. However, if I don't have explicit control over the saving (such as when I'm creating a Recipe and its Ingredients from a nested form) then I get an error: Ingredients recipe can't be blank I can get around this simply by dropping the presence validation on Ingredient.recipe. However, I don't particularly like this, as it means I'm working without a safety net. What is the best way to enforce existence-dependence in Rails? Things I'm considering (please comment on the wisdom of each): Adding a not-null constraint on the ingredients.recipe_id database column, and letting the database do the checking for me. A custom validation that somehow checks whether the Ingredient is in an unsaved recipe's ingredient collection (and thus can't have a recipe_id but is still considered valid).

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  • Out of memory while iterating through rowset

    - by Phliplip
    Hi All, I have a "small" table of 60400 rows with zipcode data. I wan't to iterate through them all, update a column value, and then save it. The following is part of my Zipcodes model which extends My_Db_Table that a totalRows function that - you guessed it.. returns the total number of rows in the table (60400 rows) public function normalizeTable() { $this->getAdapter()->setProfiler(false); $totalRows = $this->totalRows(); $rowsPerQuery = 5; for($i = 0; $i < $totalRows; $i = $i + $rowsPerQuery) { $select = $this->select()->limit($i, $rowsPerQuery); $rowset = $this->fetchAll($select); foreach ($rowset as $row) { $row->{self::$normalCityColumn} = $row->normalize($row->{self::$cityColumn}); $row->save(); } unset($rowset); } } My rowClass contains a normalize function (basicly a metaphone wrapper doing some extra magic). At first i tried a plain old $this-fetchAll(), but got a out of memory (128MB) right away. Then i tried splitting the rowset into chunks, only difference is that some rows actually gets updated. Any ideas on how i can acomplish this, or should i fallback to ye'olde mysql_query()

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  • Getting the first of a GROUP BY clause in SQL

    - by Michael Bleigh
    I'm trying to implement single-column regionalization for a Rails application and I'm running into some major headaches with a complex SQL need. For this system, a region can be represented by a country code (e.g. us) a continent code that is uppercase (e.g. NA) or it can be NULL indicating the "default" information. I need to group these items by some relevant information such as a foreign key (we'll call it external_id). Given a country and its continent, I need to be able to select only the most specific region available. So if records exist with the country code, I select them. If, not I want a records with the continent code. If not that, I want records with a NULL code so I can receive the default values. So far I've figured that I may be able to use a generated CASE statement to get an arbitrary sort order. Something like this: SELECT *, CASE region WHEN 'us' THEN 1 WHEN 'NA' THEN 2 ELSE 3 END AS region_sort FROM my_table WHERE region IN ('us','NA') OR region IS NULL GROUP BY external_id ORDER BY region_sort The problem is that without an aggregate function the actual data returned by the GROUP BY for a given row seems to be untameable. How can I massage this query to make it return only the first record of the region_sort ordered groups?

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  • Rails Model inheritance in forms

    - by Tiago
    I'm doing a reporting system for my app. I created a model ReportKind for example, but as I can report a lot of stuff, I wanted to make different groups of report kinds. Since they share a lot of behavior, I'm trying to use inheritance. So I have the main model: model ReportKind << ActiveRecord::Base end and created for example: model UserReportKind << ReportKind end In my table report_kinds I've the type column, and until here its all working. My problem is in the forms/controllers. When I do a ReportKind.new, my form is build with the '*report_kind*' prefix. If a get a UserReportKind, even through a ReportKind.find, the form will build the 'user_report_kind' prefix. This mess everything in the controllers, since sometimes I'll have params[:report_kind], sometimes params[:user_report_kind], and so on for every other inheritance I made. Is there anyway to force it to aways use the 'report_kind' prefix? Also I had to force the attribute 'type' in the controller, because it didn't get the value direct from the form, is there a pretty way to do this? Routing was another problem, since it was trying to build routes based in the inherited models names. I overcome that by adding the other models in routes pointing to the same controller.

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  • How to get the related_name of a many-to-many-field?

    - by amann
    I am trying to get the related_name of a many-to-many-field. The m2m-field is located betweeen the models "Group" and "Lection" and is declared in the group-model as following: lections = models.ManyToManyField(Lection, blank=True) The field looks like this: <django.db.models.fields.related.ManyToManyField object at 0x012AD690> The print of field.__dict__ is: {'_choices': [], '_m2m_column_cache': 'group_id', '_m2m_name_cache': 'group', '_m2m_reverse_column_cache': 'lection_id', '_m2m_reverse_name_cache': 'lection', '_unique': False, 'attname': 'lections', 'auto_created': False, 'blank': True, 'column': 'lections', 'creation_counter': 71, 'db_column': None, 'db_index': False, 'db_table': None, 'db_tablespace': '', 'default': <class django.db.models.fields.NOT_PROVIDED at 0x00FC8780>, 'editable': True, 'error_messages': {'blank': <django.utils.functional.__proxy__ object at 0x00FC 7B50>, 'invalid_choice': <django.utils.functional.__proxy__ object at 0x00FC7A50>, 'null': <django.utils.functional.__proxy__ object at 0x00FC7 A70>}, 'help_text': <django.utils.functional.__proxy__ object at 0x012AD6F0>, 'm2m_column_name': <function _curried at 0x012A88F0>, 'm2m_db_table': <function _curried at 0x012A8AF0>, 'm2m_field_name': <function _curried at 0x012A8970>, 'm2m_reverse_field_name': <function _curried at 0x012A89B0>, 'm2m_reverse_name': <function _curried at 0x012A8930>, 'max_length': None, 'name': 'lections', 'null': False, 'primary_key': False, 'rel': <django.db.models.fields.related.ManyToManyRel object at 0x012AD6B0>, 'related': <RelatedObject: mymodel:group related to lections>, 'related_query_name': <function _curried at 0x012A8670>, 'serialize': True, 'unique_for_date': None, 'unique_for_month': None, 'unique_for_year': None, 'validators': [], 'verbose_name': 'lections'} Now the field should be accessed via a lection-instance. So this is done by lection.group_set But i need to access it dynamically, so there is the need to get the related_name attribute from somewhere. Here in the documentation, there is a note that it is possible to access ManyToManyField.related_name, but this doesn't work for my somehow.. Help would be a lot appreciated. Thanks in advance.

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  • NSPopupButton Bindings with Value Transformer

    - by rdelmar
    I don't know if what I see with a popup button populated by bindings with a value transformer is the way it's supposed to be or not -- the unusual thing I'm seeing (at least with respect to what I've seen with value transformers and table views) is that the "value" parameter in the transformedValue: method is the whole array bound to the array controller, not the individual strings in the array. When I've done this with table views, the transformer is called once for each displayed row in the table, and the "value" parameter is whatever object is bound to that row and column, not the whole array that serves as the content array for the array controller. I have a very simple app to test this. In the app delegate there is this: +(void)initialize { RDTransformer *transformer = [[RDTransformer alloc] init]; [NSValueTransformer setValueTransformer:transformer forName:@"testTransformer"]; } - (void)applicationDidFinishLaunching:(NSNotification *)aNotification { self.theData = @[@{@"name":@"William", @"age":@"24"},@{@"name":@"Thomas", @"age":@"23"},@{@"name":@"Alexander", @"age":@"64"},@{@"name":@"James", @"age":@"47"}]; } In the RDTransformer class is this: + (Class)transformedValueClass { return [NSString class]; } +(BOOL)allowsReverseTransformation { return NO; } -(id)transformedValue:(id)value { NSLog(@"%@",value); return value; } In IB, I added an NSPopupButton to the window and an array controller to the objects list. The content array of the controller is bound to App Delegate.theData, and the Content Values of the popup button is bound to Array Controller.arrangedObjects.name with the value transformer, testTransformer. When I run the program, the log from the transformedValue: method is this: 2012-09-19 20:31:39.975 PopupBindingWithTransformer[793:303] ( ) 2012-09-19 20:31:40.019 PopupBindingWithTransformer[793:303] ( William, Thomas, Alexander, James ) This doesn't seem to be other people's experience from what I can see on SO. Is there something I'm doing wrong with either the bindings or the value transformer?

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  • Set focus to a button in a new TabItem

    - by Jan
    I use a TabControl to display a list of items. The ItemView is a separate control I wrote. <TabControl SelectedItem="{Binding CurrentItem}" IsSynchronizedWithCurrentItem="True" ItemsSource="{Binding ItemList}"> <TabControl.ContentTemplate> <DataTemplate> <ctrls:ItemView/> </DataTemplate> </TabControl.ContentTemplate> <TabControl.ItemTemplate> <DataTemplate> <TextBlock Text="{Binding ShortItemDescription}"/> </DataTemplate> </TabControl.ItemTemplate> </TabControl> If the user presses a Button a new ViewModel is added to the list of ViewModels and the TabControl displays it as a new tab. After adding the new tab is selected. <Button Command="{Binding AddItemCommand}" Content="Add item"/> Inside of the new ViewModel is a button that needs to be focused each time a new tab is added. I have tried to use the FocusManager and the Initialized event in the ItemView but these are only called for the first time I add a new tab. <UserControl x:Class="ItemView" ... Initialized="ViewInitialized"> <Grid> ... <!-- Set focus to this button --> <Button Content="Search" Command="{Binding SearchCommand}" Name="SearchButton" Grid.Column="0" Grid.Row="0"/> </Grid> </UserControl> Any ideas?

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  • Hibernate collection mapping Problem

    - by Geln Yang
    Hi, There is a table Item like, code,name 01,parent1 02,parent2 0101,child11 0102,child12 0201,child21 0202,child22 Create a java object and hbm xml to map the table.The Item.parent is a Item whose code is equal to the first two characters of its code : class Item{ String code; String name; Item parent; List<Item> children; .... setter/getter.... } <hibernate-mapping> <class name="Item" table="Item"> <id name="code" length="4" type="string"> <generator class="assigned" /> </id> <property name="name" column="name" length="50" not-null="true" /> <many-to-one name="parent" class="Item" not-found="ignore"> <formula> <![CDATA[ (select i.code,r.name from Item i where (case length(code) when 4 then i.code=SUBSTRING(code,1,2) else false end)) ]]> </formula> </many-to-one> <bag name="children"></bag> </class> </hibernate-mapping> I try to use formula to define the many-to-one relationship,but it doesn't work!Is there something wrong?Or is there other method? Thanks! ps,I use mysql database.

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  • Hibernate collection mapping challenge

    - by Geln Yang
    Hi, There is a table Item like, code,name 01,parent1 02,parent2 0101,child11 0102,child12 0201,child21 0202,child22 Create a java object and hbm xml to map the table.The Item.parent is a Item whose code is equal to the first two character of its code : class Item{ string code; string name; Item parent; List<Item> children; .... setter/getter.... } <hibernate-mapping> <class name="Item" table="Item"> <id name="code" length="4" type="string"> <generator class="assigned" /> </id> <property name="name" column="name" length="50" not-null="true" /> <!--====================================== --> <many-to-one name="parent" class="Item" not-found="ignore"></many-to-one> <bag name="children"></bag> <!--====================================== --> </class> </hibernate-mapping> How to definition the mapping relationship? Thanks!

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  • How do I create a simple Windows form to access a SQL Server database?

    - by NoCatharsis
    I believe this is a very novice question, and if I'm using the wrong forum to ask, please advise. I have a basic understanding of databasing with MS SQL Server, and programming with C++ and C#. I'm trying to teach myself more by setting up my own database with MS SQL Server Express 2008 R2 and accessing it via Windows forms created in C# Express 2010. At this point, I just want to keep it to free or Express dev tools (not necessarily Microsoft though). Anyway, I created a database using the instructions provided here and I set the data types appropriately for each column (no errors in setup at least). Now I'm designing the GUI in C# Express but I've kind of hit a wall as far as the database connection. Is there a simple way to access the database I created locally using C# Express? Can anyone suggest a guide that has all this spelled out already? I am a self-learner so I look forward to teaching myself how to use these applications, but any pointers to start me off in the right direction would be greatly appreciated.

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  • stored procedure issue, has to do with my where clause and if statement

    - by MyHeadHurts
    right now my stored procedure is returning 2 different result sets one for @booked and the other for @booked1 if you look closely my query is doing the same thing for each @booked and @booked but one is for a user selected year and the other for the current year. I don't want two different result sets, i want to join the selected year and the current year side by side by SDESCR(which is a column that they have in common) another hurdle i am facing is i am use @mode to decide whether the user wants netsales, sales... so on. I know i need sometype of join but, it isnt working because i have a where statement that says where dyyyy= @yeartoget which won't allow the current year data to work ALTER PROCEDURE [dbo].[test1] @mode varchar(20), @YearToGet int AS SET NOCOUNT ON Declare @Booked Int Set @Booked = CONVERT(int,DateAdd(year, @YearToGet - Year(getdate() + 1), DateAdd(day, DateDiff(day, 1, getdate()), 1) ) ) Declare @Booked1 Int Set @Booked1 = CONVERT(int,DateAdd(year, (year( getdate() )) - Year(getdate() + 1), DateAdd(day, DateDiff(day, 1, getdate()), 1) ) ) If @mode = 'Sales' Select Division, SDESCR, DYYYY, Sum(Case When Booked <= @Booked Then NetAmount End) ASofNetSales, SUM(NetAmount) AS YENetSales, Sum(Case When Booked <= @Booked Then PARTY End) AS ASofPAX, SUM(PARTY) AS YEPAX From dbo.B101BookingsDetails Where DYYYY = @YearToGet Group By SDESCR, DYYYY, Division Order By Division, SDESCR, DYYYY else if @mode = 'netsales' Select Division, SDESCR, DYYYY, Sum(Case When Booked <= @Booked Then NetAmount End) ASofNetSales, SUM(NetAmount) AS YENetSales, Sum(Case When Booked <= @Booked Then PARTY End) AS ASofPAX, SUM(PARTY) AS YEPAX From dbo.B101BookingsDetails Where DYYYY = @YearToGet Group By SDESCR, DYYYY, Division Order By Division, SDESCR, DYYYY If @mode = 'Sales' Select Division, SDESCR, DYYYY, Sum(Case When Booked <= @Booked1 Then NetAmount End) currentNetSales, Sum(Case When Booked <= @Booked1 Then PARTY End) AS currentPAX From dbo.B101BookingsDetails Where DYYYY = (year( getdate() )) Group By SDESCR, DYYYY, Division Order By Division, SDESCR, DYYYY else if @mode = 'netsales' Select Division, SDESCR, DYYYY, Sum(Case When Booked <= @Booked1 Then NetAmount End) currentNetSales, Sum(Case When Booked <= @Booked1 Then PARTY End) AS currentPAX From dbo.B101BookingsDetails Where DYYYY = (year( getdate() )) Group By SDESCR, DYYYY, Division Order By Division, SDESCR, DYYYY Else if @mode = 'Inssales' Select Division, SDESCR, DYYYY, Sum(Case When Booked <= @Booked1 Then InsAmount End) currentInsSales, Sum(Case When Booked <= @Booked1 Then PARTY End) AS currentPAX From dbo.B101BookingsDetails Where DYYYY = (year( getdate() )) Group By SDESCR, DYYYY, Division Order By Division, SDESCR, DYYYY

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  • How to change button background color depending on bound command canexecute ??

    - by LaurentH
    Hi, I Have a ItemTemplate in which is a simple button bound on a command, which can be executable or not depending on some property. I'd like the color of this button's background to change if the command isn't executable. I tried several methods, but I can't find anyway to do this purely in XAML (I'm doing this in a study context, and code behind isn't allowed). Here's my code for the button : <Button x:Name="Dispo" HorizontalAlignment="Center" Margin="0" VerticalAlignment="Center" Width="30" Height="30" Grid.Column="2" Grid.Row="0" Command="{Binding AddEmpruntCommandModel.Command}" CommandParameter="{Binding ElementName='flowCars', Path='SelectedItem'}" vm:CreateCommandBinding.Command="{Binding AddEmpruntCommandModel}" > <Button.Style> <Style TargetType="{x:Type Button}"> <Style.Triggers> <Trigger Property="IsEnabled" Value="True"> <Setter Property="Button.Background" Value="Green"/> </Trigger> <Trigger Property="IsEnabled" Value="False"> <Setter Property="Button.Background" Value="Red"/> </Trigger> </Style.Triggers> </Style> </Button.Style> </Button>

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  • how do I deconstruct COUNT()?

    - by user151841
    I have a view with some joins in it. I'm doing a select from that view with COUNT(*) as one of the columns of the select. I'm surprised by the number it's returning. Note that there is no GROUP BY nor aggregate column statement in the source view that the query is drawing from. How can I take it apart to see how it arrives at this number? I have three columns in the GROUP BY clause. SELECT column1, column2, column3, COUNT(*) FROM View GROUP BY column1, column2, column3 I get a result like +---------+---------+---------+----------+ | column1 | column2 | column3 | COUNT(*) | +---------+---------+---------+----------+ | value1 | valueA | value_a | 103 | +---------+---------+---------+----------+ | value2 | valueB | value_b | 56 | +---------+---------+---------+----------+ etc. I'd like to see how it arrives at that 103, 26, etc. In other words, I want to run a query that returns 103 rows of something, so that I know that I've expressed the query properly. I'm double-checking my work. I'm not saying that I think COUNT(*) doesn't work ( I know that "SELECT is not broken" ), what I want to double-check is exactly what I'm expressing in my query, because I think I've expressed the wrong thing, which would be why I'm getting unexpected values. I need to see more what I'm actually directing MySQL to count. So should I take them one by one, and try out each value in a WHERE clause? In other words, should I do SELECT column1 FROM View WHERE column1 = 'first_grouped_value' SELECT column1 FROM View WHERE column1 = 'second_grouped_value' SELECT column2 FROM View WHERE column1 = 'first_grouped_value' SELECT column2 FROM View WHERE column1 = 'second_grouped_value' and see the row count returned matches the COUNT(*) value in the grouped results? Because of confidentiality, I won't be able to post any of the query or database structure. All I'm asking for is a general technique to see what COUNT(*) is actually counting.

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  • What should i do for accomodating large scale data storage and retrieval?

    - by kailashbuki
    There's two columns in the table inside mysql database. First column contains the fingerprint while the second one contains the list of documents which have that fingerprint. It's much like an inverted index built by search engines. An instance of a record inside the table is shown below; 34 "doc1, doc2, doc45" The number of fingerprints is very large(can range up to trillions). There are basically following operations in the database: inserting/updating the record & retrieving the record accoring to the match in fingerprint. The table definition python snippet is: self.cursor.execute("CREATE TABLE IF NOT EXISTS `fingerprint` (fp BIGINT, documents TEXT)") And the snippet for insert/update operation is: if self.cursor.execute("UPDATE `fingerprint` SET documents=CONCAT(documents,%s) WHERE fp=%s",(","+newDocId, thisFP))== 0L: self.cursor.execute("INSERT INTO `fingerprint` VALUES (%s, %s)", (thisFP,newDocId)) The only bottleneck i have observed so far is the query time in mysql. My whole application is web based. So time is a critical factor. I have also thought of using cassandra but have less knowledge of it. Please suggest me a better way to tackle this problem.

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  • How to traverse table in Jquery and add a class?

    - by SWL
    I have a simple table of two rows. The first column is required, but the others are not; however, I would like them to be required in pairs. So if the user enters a value for Quantity3, then Size3 should also now be required. As a fiddle: http://jsfiddle.net/NaRts/7/ <tr> <td><input name="qty1[492]" class="qty required" type="text"></td> <td><input name="qty2[492]" class="qty" type="text"></td> <td><input name="qty3[492]" class="qty" type="text"></td> </tr><tr> <td><input name="size1[492]" type="text" class="size required" ></td> <td><input name="size2[492]" type="text" class="size" ></td> <td><input name="size3[492]" type="text" class="size" ></td> </tr> And the simple jQuery I have is: $('.qty').keyup(function() { var s = $(this).attr('name'); // = qty3[418] var qtyID = s.replace(/[^1-9\[\]]/g, ""); // = 3[418] var SizeID = "size" + qtyID; var $sizeInput = $(this).closest('tr').next().find(SizeID); $sizeInput.css('background-color', 'green'); $sizeInput.addClass('required'); //I tried this too but it didn't work //$(this).parent().find(SizeID).addClass('required'); });? ? Any help is much appreciated.

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  • Is it possible to filter data used by pivot table based on filtering the rows in a source table in Excel?

    - by Geoffrey Stoel
    I have developed a dashboard in Excel 2007 that uses one source table in a sheet (being filled with a query on our data warehouse) and multiple pivot tables making different cross sections on this data. I use the GETPIVOTDATA in almost a hundred formulas to give me the right value for a specific indicator in my dashboard. This all works fine. However I now have received the question to make the dashboard for 5 different segments. As you can imagine I don't want to create 5 different workbooks for this and need to maintain the dashboard logic on all of them. So my question is the following. Is it possible to automatically (through VBA or any other means) filter the results in my source table which is the source for my pivot tables and thus for my dashboard values. So schematically: DATABASE_VIEW -- SOURCE_TABLE -- 12 pivot tables -- 100 GETPIVOTDATA functions Preferably I would like to load all the segments in the source_table (one view on my database) and then filter the data in the source table, which results in filterd source_dat for my pivots. This way I can (without requerying the db) quickly change between segments in the dashboards (refreshing pivots only). Data in the source table has the column: CUSTOMER_SEGMENT available to filter upon. Any help is appreciated. Geoffrey

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  • How to prevent ADO.NET from altering double values when it reads from Excel files

    - by Khnle
    I have the following rows in my Excel input file: Column1 Column2 0-5 3.040 6 2.957 7 2.876 and the following code which uses ADO.NET to read it: string fileName = "input.xls"; var connectionString = string.Format("Provider=Microsoft.Jet.OLEDB.4.0; data source={0}; Extended Properties=Excel 8.0;", fileName); var dbConnection = new OleDbConnection(connectionString); dbConnection.Open(); try { var dbCommand = new OleDbCommand("SELECT * FROM [Sheet1$]", dbConnection); var dbReader = dbCommand.ExecuteReader (); while (dbReader.Read()) { string col1 = dbReader.GetValue(0).ToString(); string col2 = dbReader.GetValue(1).ToString(); } } finally { dbConnection.Close(); } The results are very disturbing. Here's why: The values of each column in the first time through the loop: col1 is empty (blank) col2 is 3.04016411633586 Second time: col1 is 6 col2 is 2.95722928448829 Third time: col1 is 7 col2 is 2.8763272933077 The first problem happens with col1 in the first iteration. I expect 0-5. The second problem happens at every iteration with col2 where ADO.NET obviously alters the values as it reads them. How to stop this mal-behavior?

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  • How to use MySQL geospatial extensions with spherical geometries

    - by Joshua
    Hi Everyone, I would like to store thousands of latitude/longitude points in a MySQL db. I was successful at setting up the tables and adding the data using the geospatial extensions where the column 'coord' is a Point(lat, lng). Problem: I want to quickly find the 'N' closest entries to latitude 'X' degrees and longitude 'Y' degrees. Since the Distance() function has not yet been implemented, I used GLength() function to calculate the distance between (X,Y) and each of the entries, sorting by ascending distance, and limiting to 'N' results. The problem is that this is not calculating shortest distance with spherical geometry. Which means if Y = 179.9 degrees, the list of closest entries will only include longitudes of starting at 179.9 and decreasing even though closer entries exist with longitudes increasing from -179.9. How does one typically handle the discontinuity in longitude when working with spherical geometries in databases? There has to be an easy solution to this, but I must just be searching for the wrong thing because I have not found anything helpful. Should I just forget the GLength() function and create my own function for calculating angular separation? If I do this, will it still be fast and take advantage of the geospatial extensions? Thanks! josh UPDATE: This is exactly what I am describing above. However, it is only for SQL Server. Apparently SQL Server has a Geometry and Geography datatypes. The geography does exactly what I need. Is there something similar in MySQL?

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  • Master Detail same View binding controls

    - by pipelinecache
    Hi everyone, say I have a List View with ItemControls. And a Details part that shows the selected Item from List View. Both are in the same xaml page. I tried everything to accomplish it, but what do I miss? <!-- // List --> <ItemsControl ItemsSource="{Binding Path=Model, ElementName=SomeListViewControl, Mode=Default}" SnapsToDevicePixels="True" Focusable="False" IsTabStop="False"> <ItemsControl.ItemTemplate> <DataTemplate> <SomeListView:SomeListItemControl x:Name=listItem/> </DataTemplate> </ItemsControl.ItemTemplate> </ItemsControl> <!-- // Details --> <Label Content="Begindatum" FontSize="16" VerticalAlignment="Center" Grid.Row="1" Margin="2,0,0,0"/> <TextBox x:Name="Begindatum" Grid.Column="1" Grid.Row="1" Text="{Binding Path=BeginDate, ElementName=listItem,Converter={StaticResource DateTimeConverter}, ConverterParameter=dd-MM-yyyy}" IsEnabled="False" Style="{DynamicResource TextBoxStyle}" MaxLength="30"/> public event EventHandler<DataEventArgs<SomeEntity>> OnOpenSomething; public ObservableCollection<SomeEntity> Model { get { return (ObservableCollection<SomeEntity>)GetValue(ModelProperty); } set { Model.CollectionChanged -= new NotifyCollectionChangedEventHandler(Model_CollectionChanged); SetValue(ModelProperty, value); Model.CollectionChanged += new NotifyCollectionChangedEventHandler(Model_CollectionChanged); UpdateVisualState(); } } public static readonly DependencyProperty ModelProperty = DependencyProperty.Register("Model", typeof(ObservableCollection<SomeEntity>), typeof(SomeListView), new UIPropertyMetadata(new ObservableCollection<SomeEntity>(), new PropertyChangedCallback(ChangedModel))); private static void ChangedModel(DependencyObject source, DependencyPropertyChangedEventArgs e) { SomeListView someListView = source as SomeListView; if (someListView.Model == null) { return; } CollectionView cv = (CollectionView)CollectionViewSource.GetDefaultView(someListView.Model); } private void Model_CollectionChanged(object sender, NotifyCollectionChangedEventArgs e) { if (Model == null) { return; } }

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  • How to disable the button based on Grid rows count using jquery

    - by kumar
    Hello friends, I have a button on the view.. I need to make disable based row count in the jquery grid.. that is if Rows are comming lessthen 100 I need to make Disable that button? any idea about this? here is my code.. <script type="text/javascript"> $(document).ready(function() { var RegisterGridEvents = function(excGrid) { //Register column chooser $(excGrid).jqGrid('navButtonAdd', excGrid + '_pager', { caption: "Columns", title: "Reorder Columns", onClickButton: function() { $(excGrid).jqGrid('columnChooser'); } }); $(".ui-pg-selbox").hide(); $('.ui-jqgrid-htable th:first').prepend('Select All').attr('style', 'font-size:7px'); //Register grid resize $(excGrid).jqGrid('gridResize', { minWidth: 350, maxWidth: 1500, minHeight: 400, maxHeight: 12000 }); }; $('#specialist-tab').tabs("option", "disabled", [2, 3, 4]); $('.button').button(); RegisterButtonEvents(); RegisterGridEvents("#ExceptionsGrid") }); **var a = $("#ExceptionsGrid").jqGrid('getGridParam', 'records').toString(); alert(a);** </script> is this right where I am doing this? thanks

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  • display multiple errors via bool flag c++

    - by igor
    Been a long night, but stuck on this and now am getting "segmentation fault" in my compiler.. Basically I'm trying to display all the errors (the cout) needed. If there is more than one error, I am to display all of them. bool validMove(const Square board[BOARD_SIZE][BOARD_SIZE], int x, int y, int value) { int index; bool moveError = true; const int row_conflict(0), column_conflict(1), grid_conflict(2); int v_subgrid=x/3; int h_subgrid=y/3; getCoords(x,y); for(index=0;index<9;index++) if(board[x][index].number==value){ cout<<"That value is in conflict in this row\n"; moveError=false; } for(index=0;index<9;index++) if(board[index][y].number==value){ cout<<"That value is in conflict in this column\n"; moveError=false; } for(int i=v_subgrid*3;i<(v_subgrid*3 +3);i++){ for(int j=h_subgrid*3;j<(h_subgrid*3+3);j++){ if(board[i][j].number==value){ cout<<"That value is in conflict in this subgrid\n"; moveError=false; } } } return true; }

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  • Row Prefix - ItemsControl with UniformGrid

    - by tenfour
    I am using an ItemsControl to display a List<byte> in hex. The ItemsPanelTemplate is a UniformGrid with a fixed number of columns: <ItemsControl HorizontalAlignment="Left" VerticalAlignment="Top" ItemsSource="{Binding}"> <ItemsControl.ItemsPanel> <ItemsPanelTemplate> <UniformGrid Columns="16"/> </ItemsPanelTemplate> </ItemsControl.ItemsPanel> <ItemsControl.ItemTemplate> <DataTemplate> <TextBlock Text="{Binding StringFormat='\{0:X2\}'}" Margin="5,5,5,0"/> </DataTemplate> </ItemsControl.ItemTemplate> </ItemsControl> I'd like to prefix each row with an 'Address' column, just like you'd see with the Notepad++ 'HEX-Editor' plugin. That is, since I have 16 columns, each row should be prefixed something like this: 0000 [00 01 02 .... 0F] 0010 [10 11 12 .... 1F] 0020 [20 21 22 .... 2F] ... Any suggestions?

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  • Is it better to use a relational database or document-based database for an app like Wufoo?

    - by mboyle
    I'm working on an application that's similar to Wufoo in that it allows our users to create their own databases and collect/present records with auto generated forms and views. Since every user is creating a different schema (one user might have a database of their baseball card collection, another might have a database of their recipes) our current approach is using MySQL to create separate databases for every user with its own tables. So in other words, the databases our MySQL server contains look like: main-web-app-db (our web app containing tables for users account info, billing, etc) user_1_db (baseball_cards_table) user_2_db (recipes_table) .... And so on. If a user wants to set up a new database to keep track of their DVD collection, we'd do a "create database ..." with "create table ...". If they enter some data in and then decide they want to change a column we'd do an "alter table ....". Now, the further along I get with building this out the more it seems like MySQL is poorly suited to handling this. 1) My first concern is that switching databases every request, first to our main app's database for authentication etc, and then to the user's personal database, is going to be inefficient. 2) The second concern I have is that there's going to be a limit to the number of databases a single MySQL server can host. Pretending for a moment this application had 500,000 user databases, is MySQL designed to operate this way? What if it were a million, or more? 3) Lastly, is this method going to be a nightmare to support and scale? I've never heard of MySQL being used in this way so I do worry about how this affects things like replication and other methods of scaling. To me, it seems like MySQL wasn't built to be used in this way but what do I know. I've been looking at document-based databases like MongoDB, CouchDB, and Redis as alternatives because it seems like a schema-less approach to this particular problem makes a lot of sense. Can anyone offer some advice on this?

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  • SQL indexes for "not equal" searches

    - by bortzmeyer
    The SQL index allows to find quickly a string which matches my query. Now, I have to search in a big table the strings which do not match. Of course, the normal index does not help and I have to do a slow sequential scan: essais=> \d phone_idx Index "public.phone_idx" Column | Type --------+------ phone | text btree, for table "public.phonespersons" essais=> EXPLAIN SELECT person FROM PhonesPersons WHERE phone = '+33 1234567'; QUERY PLAN ------------------------------------------------------------------------------- Index Scan using phone_idx on phonespersons (cost=0.00..8.41 rows=1 width=4) Index Cond: (phone = '+33 1234567'::text) (2 rows) essais=> EXPLAIN SELECT person FROM PhonesPersons WHERE phone != '+33 1234567'; QUERY PLAN ---------------------------------------------------------------------- Seq Scan on phonespersons (cost=0.00..18621.00 rows=999999 width=4) Filter: (phone <> '+33 1234567'::text) (2 rows) I understand (see Mark Byers' very good explanations) that PostgreSQL can decide not to use an index when it sees that a sequential scan would be faster (for instance if almost all the tuples match). But, here, "not equal" searches are really slower. Any way to make these "is not equal to" searches faster? Here is another example, to address Mark Byers' excellent remarks. The index is used for the '=' query (which returns the vast majority of tuples) but not for the '!=' query: essais=> EXPLAIN ANALYZE SELECT person FROM EmailsPersons WHERE tld(email) = 'fr'; QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------ Index Scan using tld_idx on emailspersons (cost=0.25..4010.79 rows=97033 width=4) (actual time=0.137..261.123 rows=97110 loops=1) Index Cond: (tld(email) = 'fr'::text) Total runtime: 444.800 ms (3 rows) essais=> EXPLAIN ANALYZE SELECT person FROM EmailsPersons WHERE tld(email) != 'fr'; QUERY PLAN -------------------------------------------------------------------------------------------------------------------- Seq Scan on emailspersons (cost=0.00..27129.00 rows=2967 width=4) (actual time=1.004..1031.224 rows=2890 loops=1) Filter: (tld(email) <> 'fr'::text) Total runtime: 1037.278 ms (3 rows) DBMS is PostgreSQL 8.3 (but I can upgrade to 8.4).

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