Hi All I have loaded three tables to my application. After the work is done, I want to save it all. Using 'for each' (is there a better way?), I recreated from my different class objects three data tables. Now I have the tables, I think I added them to new ds DataSet ds= new DataSet(); ds.Tables.Add(emp); ds.Tables.Add(managers); ds.Ta...
I have a data table and I want to perform a case insensitive group by over a column of data table (say Column1 of type string). I observed that normally LINQ to DataSet perform case sensitive comparison. For example if Column1 is having two values say Test and test, after applying group by it returns two seperate rows with values Test an...
It all about a typed Dataset... The 'urn:schemas-microsoft-com:xml-msdatasource:DataSetUISetting' element is not declared <?xml version="1.0" encoding="utf-8"?> <!--<autogenerated> This code was generated by a tool. Changes to this file may cause incorrect behavior and will be lost if the code is regenerated. </autogener...
For drawing Scatter plots of >100K points, Excel 2007/10 hangs under repeated refresh. What is a better tools for such tasks. I have 4 GB ram etc on this machine. ...
What is most efficient way (code example) to do an XSL transformation on a DataSet in .NET 2.0? ...
Okay, I'm accessing the fields of a data row inside a data set using indexers, but let's consider this as just a syntactical feature. Would you go so far and call it a duck typed thing that is reduced to getters and setters, in other words a data transfer object? ...
When should I use DataSet instead of DataReader? When I must use DataSet instead of DataReader? When should I use data in a disconnected fashion? When I must use data in a disconnected fashion? N.B. I am not asking which is better. I need to know the appropriate scenarios of the use of DataSet. I am programming in .net for couple o...
Hi, I have an ASP.NET web app (C#) where I get some information from a datasource and display it in the the gridview. I wanted to enable paging, but for some reason, paging doesn't work. I researched a little online, and I found that paging is done differently if a dataset is used. When I click on a page number, it refreshes, and says t...
I just realized that DBUnit doesn't create tables by itself (see How do I test with DBUnit with plain JDBC and HSQLDB without facing a NoSuchTableException?). Is there any way for DBUnit to automatically create tables from a dataset or dtd? EDIT: For simple testing of an in-memory database like HSQLDB, a crude approach can be used to ...
C# is well documented I cannot say the same about Complex Visual Components like DataGridvIew and BindingNavigator. Each time I ask a specific question about them, there are rarely answer: it seems nobody knows better than me a beginner. So instead of trying to get specific answer I'd better try to learn the whole thing so where can I f...
I'm new to vb.net and having quite a challenge with updating a field in a table using the For...Next construct on a data set. Sample code below - can anyone tell me what I'm missing? I know this particular example could be accomplished with a simple SQL update statement, but the actual use for what this code will become requires steppi...
I have a data adapter. When I check the function at runtime I see the changes, but nothing happens in the database. How do I debug this? What went wrong? OleDbDataAdapter adapter = new OleDbDataAdapter(); string queryString = "SELECT * FROM tasks"; OleDbConnection connection = new OleDbConnection(cn.ConnectionString); adapter.SelectComm...
Hi, I have the following scenario: A database A DataSet that is filled by the database Two Forms: The first Form contains a ComboBox that shows a certain set of categories. The ComboBox is binded to a DataTable "categories" in the DataSet. The second Form is supposed to be a category manager where you can add, edit and delete categor...
Hello Im using WinForms, so I have two ComboBox (cboA and cboB), cboB datasource depends of witch value is previous selected on cboA, so cboA datasource comes from a DataSet called dsDB : How can I achive this using databinding properties? Thanks ...
Hi, QUESTION 1 - What .NET classes should I be looking at to help me read / update some data in a database, but assuming I'm not using LINQ or Entity Framework. That is if you drop back to the core .net framework what are the key classes to use. In particular something that lets me access data from table X via use of C#/object type ...
Hi, Re ADO.net, I get the concept generally of DataSet and DataAdapter. What's not clear if I may ask is: Q1 - What constraints are there on whether the database connection need to remain open or not? Can I close the connection but still work with DataSet? If so what needs to be in place to perform an update? Does the DataAdapter ...
Hi, I have the following tables: Data ID ... Relationships ParentID //points to Data:ID ChildID //points to Data:ID too If I bring both the DATA and RELATIONSHIPS table into a dataset, is there a way to add the relationships into the model in a way that would add value? e.g. to enforce the constraints for example? If so I ...
Hi All, I am trying to get the DataView from a linq query expression which is querying a typed dataset. The result lands in a type of System.linq.IOrderedEnumerable. But i'm not able to convert this type to a Dataview although a few examples on the internet say that AsDataView function shoudl work but could you please throw some light o...
After working with different data sets in SAS for a month or two, it seems to me that the more variables a data set has, the more time it takes to run PROCs and other operations on the data set. Yet if I have for example 5 variables, but 1 million observations, performance is not impacted too much. While I'm interested in if observatio...
Is it possible to convert listItemcollection to dataset? Could you please give asp.net code for it? ...