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  • C Question: How to store data inside the executable file

    - by michael
    Hello all, complete newbie here, I need to find a way to store 250 KB of plain text numbers inside my program's executable file. Usually, I would put the data in a separate file and let the program read it while it is running, but that's not an option here. Instead, the program and the data need to be in one executable file. I have absolutely no idea how to do it (except writing 250.000 #defines :-) and I'd appreciate any suggestions. Thank you very much!

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  • Merge two data frames together that have the same variable names and data types

    - by Brandon
    I have tried the merge function to merge two csv files that I imported. They both have the same variable names and data types but each time I run merge all that I get is an object that contains the names of the two data frames. I have tried the following: # ex1 obj <- merge(obj1, obj2, by=obj) # ex2 obj <- merge(obj1, obj2, all) and several other iterations of the above. Is merge the correct function? If so, what am I doing wrong?

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  • How to manually add Core Data to project?

    - by marko
    E.g. what "Use Core Data for storage" checkbox option means when creating new Window or Navigation based project? How to add Core Data for Tab Bar Application? How to initialize managedObjectModel, managedObjectContext, persistentStoreCoordinator?

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  • Delphi, read data from 3rd party data field

    - by donaldadams1951
    I am writing an application that needs to read a data field on another Delphi program and I do not have access to the source code of the 3rd party program. The data field contains the "foreign key" to a record I need to retrieve or create in my application. I would appreciate any links to knowledge or components that will help me with my program.

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  • Isolate large amounts of data w/ jQuery

    - by Bry4n
    I work for a transit agency and I have large amounts of data (mostly times), and I need a way to filter the data using two textboxes (To and From). I found jQuery quick search, but it seems to only work with one textbox. If anyone has any ideas via jQuery or some other client side library, that would be fantastic.

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  • pass string or data of local file between viewcontrollers

    - by Jonathan
    In my last question i asked how to best send a string from one view controller to another, both which were on a navigation stack: http://stackoverflow.com/questions/2898860/pass-string-from-tableviewcontroller-to-viewcontroller-in-navigation-stack However I just realised I can either pass the path to the file in the app's document's folder as the first (the table view) has already accessed the data in the file should I pass viewcontroller the data to the pushed VC?

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  • Data Storage question

    - by Nano8Blazex
    Another newbie question: What's the best way to store data in a Cocoa application written in Obj-C? For example if I want to create a sort of "quizzer" that quizzes the user with pre-written (and user-written) questions? How would I store these questions and answers? Core Data? Thanks!

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  • Possible ways of representing data in memory (.net)

    - by This is it
    Hi What are the possible ways of representing data in memory in .Net (or in general)? It would be great if data could be sorted and looked up by key (or multiple keys). We are thinking to use collections, arrays, list of collections/arrays. One object would be in several collections (one sorted asc, other desc, etc.). Maybe this is not a good idea, and we would like to hear some other possible solutions. Thank you

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  • Stumbling Through: Visual Studio 2010 (Part III)

    The last post ended with us just getting started on stumbling into text template file customization, a task that required a Visual Studio extension (Tangible T4 Editor) to even have a chance at completing.  Despite the benefits of the Tangible T4 Editor, I still had a hard time putting together a solid text template that would be easy to explain.  This is mostly due to the way the files allow you to mix code (encapsulated in <# #>) with straight-up text to generate.  It is effective to be sure, but not very readable.  Nevertheless, I will try and explain what was accomplished in my custom tt file, though the details of which are not really the point of this article (my way of saying dont criticize my crappy code, and certainly dont use it in any somewhat real application.  You may become dumber just by looking at this code.  You have been warned really the footnote I should put at the end of all of my blog posts). To begin with, there were two basic requirements that I needed the code generator to satisfy:  Reading one to many entity framework files, and using the entities that were found to write one to many class files.  Thankfully, using the Entity Object Generator as a starting point gave us an example on how to do exactly that by using the MetadataLoader and EntityFrameworkTemplateFileManager you include references to these items and use them like so: // Instantiate an entity framework file reader and file writer MetadataLoader loader = new MetadataLoader(this); EntityFrameworkTemplateFileManager fileManager = EntityFrameworkTemplateFileManager.Create(this); // Load the entity model metadata workspace MetadataWorkspace metadataWorkspace = null; bool allMetadataLoaded =loader.TryLoadAllMetadata("MFL.tt", out metadataWorkspace); EdmItemCollection ItemCollection = (EdmItemCollection)metadataWorkspace.GetItemCollection(DataSpace.CSpace); // Create an IO class to contain the 'get' methods for all entities in the model fileManager.StartNewFile("MFL.IO.gen.cs"); Next, we want to be able to loop through all of the entities found in the model, and then each property for each entity so we can generate classes and methods for each.  The code for that is blissfully simple: // Iterate through each entity in the model foreach (EntityType entity in ItemCollection.GetItems<EntityType>().OrderBy(e => e.Name)) {     // Iterate through each primitive property of the entity     foreach (EdmProperty edmProperty in entity.Properties.Where(p => p.TypeUsage.EdmType is PrimitiveType && p.DeclaringType == entity))     {         // TODO:  Create properties     }     // Iterate through each relationship of the entity     foreach (NavigationProperty navProperty in entity.NavigationProperties.Where(np => np.DeclaringType == entity))     {         // TODO:  Create associations     } } There really isnt anything more advanced than that going on in the text template the only thing I had to blunder through was realizing that if you want the generator to interpret a line of code (such as our iterations above), you need to enclose the code in <# and #> while if you want the generator to interpret the VALUE of code, such as putting the entity name into the class name, you need to enclose the code in <#= and #> like so: public partial class <#=entity.Name#> To make a long story short, I did a lot of repetition of the above to come up with a text template that generates a class for each entity based on its properties, and a set of IO methods for each entity based on its relationships.  The two work together to provide lazy-loading for hierarchical data (such getting Team.Players) so it should be pretty intuitive to use on a front-end.  This text template is available here you can tweak the inputFiles array to load one or many different edmx models and generate the basic xml IO and class files, though it will probably only work correctly in the simplest of cases, like our MFL model described in the previous post.  Additionally, there is no validation, logging or error handling which is something I want to handle later by stumbling through the enterprise library 5.0. The code that gets generated isnt anything special, though using the LINQ to XML feature was something very new and exciting for me I had only worked with XML in the past using the DOM or XML Reader objects along with XPath, and the LINQ to XML model is just so much more elegant and supposedly efficient (something to test later).  For example, the following code was generated to create a Player object for each Player node in the XML:         return from element in GetXmlData(_PlayerDataFile).Descendants("Player")             select new Player             {                 Id = int.Parse(element.Attribute("Id").Value)                 ,ParentName = element.Parent.Name.LocalName                 ,ParentId = long.Parse(element.Parent.Attribute("Id").Value)                 ,Name = element.Attribute("Name").Value                 ,PositionId = int.Parse(element.Attribute("PositionId").Value)             }; It is all done in one line of code, no looping needed.  Even though GetXmlData loads the entire xml file just like the old XML DOM approach would have, it is supposed to be much less resource intensive.  I will definitely put that to the test after we develop a user interface for getting at this data.  Speaking of the data where IS the data?  Weve put together a pretty model and a bunch of code around it, but we dont have any data to speak of.  We can certainly drop to our favorite XML editor and crank out some data, but if it doesnt totally match our model, it will not load correctly.  To help with this, Ive built in a method to generate xml at any given layer in the hierarchy.  So for us to get the closest possible thing to real data, wed need to invoke MFL.IO.GenerateTeamXML and save the results to file.  Doing so should get us something that looks like this: <Team Id="0" Name="0">   <Player Id="0" Name="0" PositionId="0">     <Statistic Id="0" PassYards="0" RushYards="0" Year="0" />   </Player> </Team> Sadly, it is missing the Positions node (havent thought of a way to generate lookup xml yet) and the data itself isnt quite realistic (well, as realistic as MFL data can be anyway).  Lets manually remedy that for now to give us a decent starter set of data.  Note that this is TWO xml files Lookups.xml and Teams.xml: <Lookups Id=0>   <Position Id="0" Name="Quarterback"/>   <Position Id="1" Name="Runningback"/> </Lookups> <Teams Id=0>   <Team Id="0" Name="Chicago">     <Player Id="0" Name="QB Bears" PositionId="0">       <Statistic Id="0" PassYards="4000" RushYards="120" Year="2008" />       <Statistic Id="1" PassYards="4200" RushYards="180" Year="2009" />     </Player>     <Player Id="1" Name="RB Bears" PositionId="1">       <Statistic Id="2" PassYards="0" RushYards="800" Year="2007" />       <Statistic Id="3" PassYards="0" RushYards="1200" Year="2008" />       <Statistic Id="4" PassYards="3" RushYards="1450" Year="2009" />     </Player>   </Team> </Teams> Ok, so we have some data, we have a way to read/write that data and we have a friendly way of representing that data.  Now, what remains is the part that I have been looking forward to the most: present the data to the user and give them the ability to add/update/delete, and doing so in a way that is very intuitive (easy) from a development standpoint.Did you know that DotNetSlackers also publishes .net articles written by top known .net Authors? We already have over 80 articles in several categories including Silverlight. Take a look: here.

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  • Stumbling Through: Visual Studio 2010 (Part III)

    The last post ended with us just getting started on stumbling into text template file customization, a task that required a Visual Studio extension (Tangible T4 Editor) to even have a chance at completing.  Despite the benefits of the Tangible T4 Editor, I still had a hard time putting together a solid text template that would be easy to explain.  This is mostly due to the way the files allow you to mix code (encapsulated in <# #>) with straight-up text to generate.  It is effective to be sure, but not very readable.  Nevertheless, I will try and explain what was accomplished in my custom tt file, though the details of which are not really the point of this article (my way of saying dont criticize my crappy code, and certainly dont use it in any somewhat real application.  You may become dumber just by looking at this code.  You have been warned really the footnote I should put at the end of all of my blog posts). To begin with, there were two basic requirements that I needed the code generator to satisfy:  Reading one to many entity framework files, and using the entities that were found to write one to many class files.  Thankfully, using the Entity Object Generator as a starting point gave us an example on how to do exactly that by using the MetadataLoader and EntityFrameworkTemplateFileManager you include references to these items and use them like so: // Instantiate an entity framework file reader and file writer MetadataLoader loader = new MetadataLoader(this); EntityFrameworkTemplateFileManager fileManager = EntityFrameworkTemplateFileManager.Create(this); // Load the entity model metadata workspace MetadataWorkspace metadataWorkspace = null; bool allMetadataLoaded =loader.TryLoadAllMetadata("MFL.tt", out metadataWorkspace); EdmItemCollection ItemCollection = (EdmItemCollection)metadataWorkspace.GetItemCollection(DataSpace.CSpace); // Create an IO class to contain the 'get' methods for all entities in the model fileManager.StartNewFile("MFL.IO.gen.cs"); Next, we want to be able to loop through all of the entities found in the model, and then each property for each entity so we can generate classes and methods for each.  The code for that is blissfully simple: // Iterate through each entity in the model foreach (EntityType entity in ItemCollection.GetItems<EntityType>().OrderBy(e => e.Name)) {     // Iterate through each primitive property of the entity     foreach (EdmProperty edmProperty in entity.Properties.Where(p => p.TypeUsage.EdmType is PrimitiveType && p.DeclaringType == entity))     {         // TODO:  Create properties     }     // Iterate through each relationship of the entity     foreach (NavigationProperty navProperty in entity.NavigationProperties.Where(np => np.DeclaringType == entity))     {         // TODO:  Create associations     } } There really isnt anything more advanced than that going on in the text template the only thing I had to blunder through was realizing that if you want the generator to interpret a line of code (such as our iterations above), you need to enclose the code in <# and #> while if you want the generator to interpret the VALUE of code, such as putting the entity name into the class name, you need to enclose the code in <#= and #> like so: public partial class <#=entity.Name#> To make a long story short, I did a lot of repetition of the above to come up with a text template that generates a class for each entity based on its properties, and a set of IO methods for each entity based on its relationships.  The two work together to provide lazy-loading for hierarchical data (such getting Team.Players) so it should be pretty intuitive to use on a front-end.  This text template is available here you can tweak the inputFiles array to load one or many different edmx models and generate the basic xml IO and class files, though it will probably only work correctly in the simplest of cases, like our MFL model described in the previous post.  Additionally, there is no validation, logging or error handling which is something I want to handle later by stumbling through the enterprise library 5.0. The code that gets generated isnt anything special, though using the LINQ to XML feature was something very new and exciting for me I had only worked with XML in the past using the DOM or XML Reader objects along with XPath, and the LINQ to XML model is just so much more elegant and supposedly efficient (something to test later).  For example, the following code was generated to create a Player object for each Player node in the XML:         return from element in GetXmlData(_PlayerDataFile).Descendants("Player")             select new Player             {                 Id = int.Parse(element.Attribute("Id").Value)                 ,ParentName = element.Parent.Name.LocalName                 ,ParentId = long.Parse(element.Parent.Attribute("Id").Value)                 ,Name = element.Attribute("Name").Value                 ,PositionId = int.Parse(element.Attribute("PositionId").Value)             }; It is all done in one line of code, no looping needed.  Even though GetXmlData loads the entire xml file just like the old XML DOM approach would have, it is supposed to be much less resource intensive.  I will definitely put that to the test after we develop a user interface for getting at this data.  Speaking of the data where IS the data?  Weve put together a pretty model and a bunch of code around it, but we dont have any data to speak of.  We can certainly drop to our favorite XML editor and crank out some data, but if it doesnt totally match our model, it will not load correctly.  To help with this, Ive built in a method to generate xml at any given layer in the hierarchy.  So for us to get the closest possible thing to real data, wed need to invoke MFL.IO.GenerateTeamXML and save the results to file.  Doing so should get us something that looks like this: <Team Id="0" Name="0">   <Player Id="0" Name="0" PositionId="0">     <Statistic Id="0" PassYards="0" RushYards="0" Year="0" />   </Player> </Team> Sadly, it is missing the Positions node (havent thought of a way to generate lookup xml yet) and the data itself isnt quite realistic (well, as realistic as MFL data can be anyway).  Lets manually remedy that for now to give us a decent starter set of data.  Note that this is TWO xml files Lookups.xml and Teams.xml: <Lookups Id=0>   <Position Id="0" Name="Quarterback"/>   <Position Id="1" Name="Runningback"/> </Lookups> <Teams Id=0>   <Team Id="0" Name="Chicago">     <Player Id="0" Name="QB Bears" PositionId="0">       <Statistic Id="0" PassYards="4000" RushYards="120" Year="2008" />       <Statistic Id="1" PassYards="4200" RushYards="180" Year="2009" />     </Player>     <Player Id="1" Name="RB Bears" PositionId="1">       <Statistic Id="2" PassYards="0" RushYards="800" Year="2007" />       <Statistic Id="3" PassYards="0" RushYards="1200" Year="2008" />       <Statistic Id="4" PassYards="3" RushYards="1450" Year="2009" />     </Player>   </Team> </Teams> Ok, so we have some data, we have a way to read/write that data and we have a friendly way of representing that data.  Now, what remains is the part that I have been looking forward to the most: present the data to the user and give them the ability to add/update/delete, and doing so in a way that is very intuitive (easy) from a development standpoint.Did you know that DotNetSlackers also publishes .net articles written by top known .net Authors? We already have over 80 articles in several categories including Silverlight. Take a look: here.

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  • Transferring data from Salesforce using Apex Data Loader to Oracle

    - by Barret
    While attempting to transfer data from Salesforce using Apex Data Loader to Oracle Keep getting the following error: 26937 [databaseAccountExtract] FATAL com.salesforce.dataloader.dao.database.Data baseContext - Error getting value for SQL parameter: nkey__c. Please make sure that the value exists in the configuration file or is passed in. Database conf iguration: insertAccount. The database-conf.xml has the following beans: <bean id="insertAccount" class="com.salesforce.dataloader.dao.database.DatabaseConfig" singleton="true"> <property name="sqlConfig" ref="insertAccountSql"/> <property name="dataSource" ref="dbDataSource"/> </bean> <bean id="insertAccountSql" class="com.salesforce.dataloader.dao.database.SqlConfig" singleton="true"> <property name="sqlString"> <value> INSERT INTO VANTROPO.SF_ACCOUNTCHANNEL (nkey__c) VALUES (@nkey__c@) </value> </property> <property name="sqlParams"> <map> <entry key="nkey__c" value="java.lang.String"/> </map> </property> </bean> The SDL (mapping file) has the following values: # Account Insert Mapping values for query from Salesforce (left) and insert/update to Oracle (right) # SalesforceFieldName=OracleFieldName nkey__c=NKEY__C Any help appreciated.

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  • Error using Dynamic Data Filtering: missing datasource

    - by sebastiaan
    I am trying to use the ASP.NET Dynamic Data Filtering project, but I'm running into a problem during the configuration. I'm following the instructions on the author's blog, and everything works like described. Then it tells me to change the datasource using the designer view. I am told to select the "GridDataSource" in the "Configure data source" wizard. This option is not there though. I get all of the classes in my project, including the DataContext that was generated by Linq. When I choose "Show only DataContext objects", the dropdown ("Choose your context object:") is completely empty. When I turn of the checkbox and choose my DataContext class, I get asked which table I want and all that. But, as the whole purpose of a Dynamic Data site is NOT to use one single table, that's not much help. So I've looked at the instructions again and copied the resulting datasource from the example: <asp:DynamicLinqDataSource ID="GridDataSource" runat="server" EnableDelete="True" EnableUpdate="True"></asp:DynamicLinqDataSource> Which is exactly what I had, without the "WhereParameters" nodes in there. Now, when I run the list page however, I get an exception about a missing datasource from the filtering component. Of course when I remove the DynamicFilterRepeater, it works again. This is the meat of the exception: [InvalidOperationException: Missing DataSource] Catalyst.Web.DynamicData.DynamicFilterRepeater.GetTable() in D:\Catalyst\Projects\DynamicData\Project\Trunk\DynamicData\DynamicData\DynamicFilterRepeater.cs:74 Catalyst.Web.DynamicData.DynamicFilterRepeater.GetFilters() in D:\Catalyst\Projects\DynamicData\Project\Trunk\DynamicData\DynamicData\DynamicFilterRepeater.cs:81 Catalyst.Web.DynamicData.DynamicFilterRepeater.OnInit(EventArgs e) in D:\Catalyst\Projects\DynamicData\Project\Trunk\DynamicData\DynamicData\DynamicFilterRepeater.cs:106 How do I make the DynamicFilterRepeater recognize my datasource? I'm using VS2010 Pro, on a Win7 machine.

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  • asp.net Dynamic Data Site with own MetaData

    - by loviji
    Hello, I'm searching info about configuring own MetaData in asp.NET Dynamic Site. For example. I have a table in MS Sql Server with structure shown below: CREATE TABLE [dbo].[someTable]( [id] [int] NOT NULL, [pname] [nvarchar](20) NULL, [FullName] [nvarchar](50) NULL, [age] [int] NULL) and I there are 2 Ms Sql tables (I've created), sysTables and sysColumns. sysTables: ID sysTableName TableName TableDescription 1 | someTable |Persons |All Data about Persons in system sysColumns: ID TableName sysColumnName ColumnName ColumnDesc ColumnType MUnit 1 |someTable | sometable_pname| Name | Persona Name(ex. John)| nvarchar(20) | null 2 |someTable | sometable_Fullname| Full Name | Persona Name(ex. John Black)| nvarchar(50) | null 3 |someTable | sometable_age| age | Person age| int | null I want that, in Details/Edit/Insert/List/ListDetails pages use as MetaData sysColumns and sysTableData. Because, for ex. in DetailsPage fullName, it is not beatiful as Full Name . someIdea, is it possible? thanks Updated:: In List Page to display data from sysTables (metaData table) I've modified <h2 class="DDSubHeader"><%= tableName%></h2>. public string tableName; protected void Page_Init(object sender, EventArgs e) { table = DynamicDataRouteHandler.GetRequestMetaTable(Context); //added by me uqsikDataContext sd=new uqsikDataContext(); tableName = sd.sysTables.Where(n => n.sysTableName == table.DisplayName).FirstOrDefault().TableName; //end GridView1.SetMetaTable(table, table.GetColumnValuesFromRoute(Context)); GridDataSource.EntityTypeName = table.EntityType.AssemblyQualifiedName; if (table.EntityType != table.RootEntityType) { GridQueryExtender.Expressions.Add(new OfTypeExpression(table.EntityType)); } } so, what about sysColums? How can I get Data from my sysColumns table?

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  • RESTful WCF Data Service Authentication

    - by Adrian Grigore
    Hi, I'd like to implement a REST api to an existing ASP.NET MVC website. I've managed to set up WCF Data services so that I can browse my data, but now the question is how to handle authentication. Right now the data service is secured via the site's built in forms authentication, and that's ok when accessing the service from AJAX forms. However, It's not ideal for a RESTful api. What I would like as an alternative to forms authentication is for the users to simply embed the user name and password into the url to the web service or as request parameters. For example, if my web service is usually accessible as http://localhost:1234/api.svc I'd like to be able to access it using the url http://localhost:1234/api.svc/{login}/{password} So, my questions are as follows: Is this a sane approach? If yes, how can I implement this? It seems trivial redirecting GET requests so that the login and password are attached as GET parameters. I also know how to inspect the http context and use those parameters to filter the results. But I am not sure if / how the same approach could be applied to POST, PUT and DELETE requests. Thanks, Adrian

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  • Data loss when downloading data from LDAP server

    - by Ricky D'Amelio
    Hi there. This question comes from a previous one I asked about handling NSData objects: http://stackoverflow.com/questions/2453785/converting-nsdata-to-an-nsstring-representation-is-failing. I have reached the point where I am taking an NSImage, turning it into NSData and uploading those data bytes to the LDAP server. I am doing this like so; //connected successfully to LDAP server above... struct berval photo_berval; struct berval *jpegPhoto_values[2]; photo_berval.bv_len = [photo length]; photo_berval.bv_val = [photo bytes]; jpegPhoto_values[0] = &photo_berval; jpegPhoto_values[1] = NULL; mod.mod_type = "jpegPhoto"; mod.mod_op = LDAP_MOD_REPLACE|LDAP_MOD_BVALUES; mod.mod_bvalues = jpegPhoto_values; mods[0] = &mod; mods[1] = NULL; //perform the modify operation rc = ldap_modify_ext_s(ld, givenModifyEntry, mods, NULL, NULL); That happens with no errors, and you can see a big blob of data when you're in the command line. My problem is, when I go to access the same data at a later stage, I am getting an image file back that's about 120 times smaller than the original image. //find the jpegPhoto attribute photoA = ldap_first_attribute(ld, photoE, &photoBer); while (strcasecmp(photoA, "jpegphoto") != 0) { photoA = ldap_next_attribute(ld, photoE, photoBer); } //get the value of the attribute if ((list_of_photos = ldap_get_values_len(ld, photoE, photoA)) != NULL) { //get the first JPEG photo_data = *list_of_photos[0]; selectedPictureData = [NSData dataWithBytes:&photo_data length:sizeof(photo_data)]; [selectedPictureData writeToFile:@"/Users/username/Desktop/Photo 2.jpg" atomically:YES]; NSLog (@"%@", selectedPictureData); Has anyone successfully done this before or can anyone see what I might be doing wrong? I appreciate anyone's help. Sorry to post so many questions! Ricky.

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  • Jasper report exports empty data in PDF format when there is more data

    - by stanley
    I have a report to be exported in excel, pdf and word using jasper reports. I use xml file as the DataSource for the report, but when the data increases jasper report exports empty file in only for PDF format, when i reduce the data content it export the data available correctly. is there any limitation to pdf size? , how can we manage the size in jasper reports from java? My jrxml is really big, so i cannot add it here, i have added my java code which i use to export the content:- JRAbstractExporter exporter = null; if (format.equals("pdf")) { exporter = new JRPdfExporter(); jasperPrint.setPageWidth(Integer.parseInt( pWidth )); } else if (format.equals("xls")) { exporter = new JRXlsExporter(); } else if (format.equals("doc")) { jasperPrint.setPageWidth(Integer.parseInt( pWidth )); } exporter.setParameter(JRExporterParameter.JASPER_PRINT, jasperPrint); exporter.setParameter(JRExporterParameter.OUTPUT_STREAM, outputStream_); exporter.exportReport(); contents = outputStream_.toByteArray(); response.setContentType("application/"+format); response.addHeader("Content-disposition", "attachment;filename=" + name.toString() + "."+format);

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  • Pros and cons of making database IDs consistent and "readable"

    - by gmale
    Question Is it a good rule of thumb for database IDs to be "meaningless?" Conversely, are there significant benefits from having IDs structured in a way where they can be recognized at a glance? What are the pros and cons? Background I just had a debate with my coworkers about the consistency of the IDs in our database. We have a data-driven application that leverages spring so that we rarely ever have to change code. That means, if there's a problem, a data change is usually the solution. My argument was that by making IDs consistent and readable, we save ourselves significant time and headaches, long term. Once the IDs are set, they don't have to change often and if done right, future changes won't be difficult. My coworkers position was that IDs should never matter. Encoding information into the ID violates DB design policies and keeping them orderly requires extra work that, "we don't have time for." I can't find anything online to support either position. So I'm turning to all the gurus here at SA! Example Imagine this simplified list of database records representing food in a grocery store, the first set represents data that has meaning encoded in the IDs, while the second does not: ID's with meaning: Type 1 Fruit 2 Veggie Product 101 Apple 102 Banana 103 Orange 201 Lettuce 202 Onion 203 Carrot Location 41 Aisle four top shelf 42 Aisle four bottom shelf 51 Aisle five top shelf 52 Aisle five bottom shelf ProductLocation 10141 Apple on aisle four top shelf 10241 Banana on aisle four top shelf //just by reading the ids, it's easy to recongnize that these are both Fruit on Aisle 4 ID's without meaning: Type 1 Fruit 2 Veggie Product 1 Apple 2 Banana 3 Orange 4 Lettuce 5 Onion 6 Carrot Location 1 Aisle four top shelf 2 Aisle four bottom shelf 3 Aisle five top shelf 4 Aisle five bottom shelf ProductLocation 1 Apple on aisle four top shelf 2 Banana on aisle four top shelf //given the IDs, it's harder to see that these are both fruit on aisle 4 Summary What are the pros and cons of keeping IDs readable and consistent? Which approach do you generally prefer and why? Is there an accepted industry best-practice?

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