dataset

问题 setwd("C:\\Users\\DATA") temp = list.files(pattern="*.dta") for (i in 1:length(temp)) assign(temp[i], read.dta13(temp[i], nonint.factors = TRUE)) grep(pattern="_m", temp, value=TRUE) Here I create a list of my datasets and read them into R, I then attempt to use grep in order to find all variable names with pattern _m, obviously this doesn't work because this simply returns all filenames with pattern _m. So essentially what I want, is my code to loop through the list of databases, find

问题 I have created three data tables by pulling data from an sql database. DT1, DT2, DT3. I have added these three tables to a data set, myDS. I have added relations between these three tables. I then dragged a DataGridView onto my form and I want to bind the three tables to the DataGridview. So I added my dataset DS to a dataview manager, myDVM. I bound myDVM to a bindingsource, bindingSource1, and made it the data source for the DataGridView. I am not sure how to bind the tables I want from

问题 I have a SQL Server Database with several tables. One of them has "ID" (primary key), "Name" and other columns that i won't mention here for sake of simplicity. "ID" column is auto increment, unique and when i add some row using "SQL Server management studio", "ID" column increments properly. Database is old and current auto increment is at 1244 or so. Now, i have created a C# project that uses TYPED Dataset to work with data from database. My database starts empty, dataset is filled using

问题 This article here describes handling concurrency exceptions. The steps to reproduce the problem are: Create a new Windows Application project. Create a new dataset based on the Northwind Customers table. Create a form with a DataGridView to display the data. Fill a dataset with data from the Customers table in the Northwind database. After filling the dataset, use the Visual Database Tools in Visual Studio to directly access the Customers data table and change a record. Then on the form,

问题 I am converting dataset to a Dynamic collection and binding it, this is working fine.Now when i need to add a new object which is empty to the collection . what i am trying is getting the ItemsSource of the datagrid and getting the first object inside the list. But it has some values inside it. How can i remove the values and bind a empty object using reflection. Here is my code, IEnumerable<object> collection = this.RetrieveGrid.ItemsSource.Cast<object>(); List<object> list = collection

问题 I'm trying to insert a dataset into an SQL database but I am having difficulties passing my dataset as an argument to my DB class. I am not sure if it is allowed to pass as an argument. If not, what are my alternatives? The way I create my dataset: public static void getLogs() { string path = Environment.GetFolderPath(Environment.SpecialFolder.ApplicationData) + @"\someDir"; SQLiteConnection cn = new SQLiteConnection("Data Source=" + path + ";Version=3;New=False;Compress=True;"); cn.Open();

问题 I am using Object class( public static List<Restaurant> res; ) to set data that I am getting json data from server. The flow of the app is as follow. Step 1: (MainActivity.class) Getting data from server Step 2: Set all the Json data into List<Object> class. And declared List<Object> as a public static in MainActivity Step 3: Here I need to populate List<Object> class values into the Recyclerview.Due to declared as public static, I called this directly while setting in adapter in a fragment

问题 In my project there are two datasets dsNames and dsDetails . I dont know about SQL. Here I am connecting to XML and Textfiles. dtNames EmployeeName EmployeeRole a 2 b 3 c 4 dtDetails Empid EmployeeName EmpCity EmployeeRole 101 a abc 3 //EmpRole not equal to above table EmpRole 102 b abc 3 103 c xyz 4 104 d pqr 5 105 e rst 6 I want to relate these two datasets based on the EmployeeName and EmployeeRole (here comparing to dsNames ) and store the result in another DataSet dsMain (table from

问题 I have a stored procedures which returns about 5 tables and I am returning them something like this: select <fields> from Products where ProductId = @ProductId select <fields> from RelatedProducts where ProductId = @ProductId select <fields> from MetaData where ProductId = @ProductId well, you get the gist. Now in the Dataset, If I do this: DataSet ProductDs = DAL.RetreiveProductMetadata(someInteger); ProductName = DataSet.Tables["Products"].Rows[0]["columnName"].ToString(); Its throwing up

问题 This question is unlikely to help any future visitors; it is only relevant to a small geographic area, a specific moment in time, or an extraordinarily narrow situation that is not generally applicable to the worldwide audience of the internet. For help making this question more broadly applicable, visit the help center. Closed 6 years ago . In C#,i have a huge dataset that i want to write it into xml file with write xml,that is my code: using (var myConnection = new SqlConnection("Data