C# - Design Question - DataSet Or List - Update Changes
Aug 5, 2009
Not sure if I have the correct subject line. Here is my issue. I have a form with 2 GridView. One GridView has a list of all zipCodes. The users is to select a location from a dropdown list, then select the zipcodes he/she wants to be assigned to that location and then click the "Add" button. The zipcodes then appear in the second GridView. When the user clicks the "Save" button, the data is sent to the database. The is also a "Remove" to remove zipcode(s) in the second GridView.
How do I track changes only in the second GridView. There could be 1000's of zipcode in the second GridView. Do I just remove and re-insert the list for that location evertime the user click save? I was thinking of using a DataSet, add DataRows and then update, however I am not using a DataAdapter to load my dataset, so there is no way for me to use DataAdapter.Update(ds). I am using the SQLHelper.ExecuteDataset(parms)
I have some concern about designing Datasets. I was told that it would be good to have a dataset for each table for maintenance purpose. Because frequent change in database tables is expected, having one dataset including every tables would be pain to make the corresponding change in the application.
Q. is it good approach to have a dataset for each table ( I would end up having 30~40 datasets for each db table using Stored procedure) ?
I have a separate project for commonly used datasets. each project include "dataset project" as a reference, and use it by including needed dataset into Forms, classes, etc.
Q. Does this approach makes the whole system to be slower? If I have a set of datasets as a separate project, it would be beneficial, since It will be easier to make a change (I only need to make modification in one place)
I have a small dataset which has most of its schema defined at design time, but I add a few columns to one of its tables at runtime. My problem is how do I reset those changes? he dataset is not linked to any datasource. It just has its own table which I "manually" populate. The static columns have been added to the datatable at design time. However, I add a few columns as runtime based on a list of categories. Like this:
[Code]....
The dataset is used in a small dialog that pops up within my application. I add the dynamic columns when the dialog is opened by using the Load event. Everything works great the first time. But if you close the dialog and reopen it, there are problems. My startup routine tries adding the dynamic columns again, but an error is thrown saying the column already exists. I have tried a lot of things and did some reading but I can't figure out a way to reset the dataset when the dialog is closed. The only solution is to close the whole application and reopen it. I have tried the following in the Leave event of the dialog form:
I think (?) this is about object design, and perhaps about structural and/or creational patterns. But a bit hard to say when I only know a couple of patterns yet.[code]But... what if we INSTEAD want each Product instance only to (in some way) refer to one instance of a specific list of Components. So we wan't to save the products list to one file, and the components list to another file. Then would I build the objects the same way, or different? So let's then say we have now Class B as below. [code]
1. Will not need to update each component variable of the products list when the components list changes.
2. If the Product object shall be shown in a DataGridView, for editing properties, it seems easier to implement the selection of the component property.
Is this wrong approach? Is it suitable in some cases, and if so, when? Are there other solutions I perhaps am not aware of that would be appropriate? Is this about structural design patterns? and if so, can the alternatives above be catagorized to some pattern type? I don't really know exactly what I'm looking for.. But I think probably I'm looking to understand whether the object design will be determined by the way the objects are saved.. And if i shall save the objects by serializing to file, vs saving to a database, would I create the business objects differently?
I have had some reall problems with this. I have a form with a datagridview, now I can add new records and the dataset will update fine, but it wont update when I want to delete a record.[code]...
Im using a dataset to add records into an xml file.what i want to know is... can you use a dataset to update a existing record in the xml file?if so can i get the dataset/row to reference the specific "record id" i am wanting to amend?
Let say I have a function inside a class which require 4 parameter (table name,field name,field value, return field) When I use this function my form, such as
myclass.Search("customers", <-- after pressing the "," a popup list will be displayed that contain all the fields in "customers" table.
I have been on this for a week, with no luck, I keep getting the same error at the same place. IBasically, I join 3 tables together for reporting, I update one of the tables while reading thru, after I want the updates to stay.The error is something like "Update requires valid update command on Datarow".[code]
Today i have been checking out the concept of datasets and i like the way they work except for a minor issue i have with it.The following code should get a databasetable and put it in a dataset and return that set to the user.[code]I submit the table name and it will select it, read it and fill the dataset with it, then return it. And it does exactly that once.If i try to re-read the same datatable it just returns the exact same dataset as the first time yet i am 100000% sure that i changed it .
So I'm not familiar with much vb code but I was hoping someone my spell out something pretty generic as far as updating a database. I'm pretty sure I've successfully edited rows but when i'm using my database update i get an error, probably just incorrect syntax. This is what I have so far...
I have been answering question about updating Table or DataBase Using DGV. Most the people still having problem about it. Being honest with all of you, I don't know why?
I have been stuck on this for the last 30 min, can't find out where I am going wrong. Its fully functional scrolling through records but I get an error when I try to update a record. The error is "Update requires a valid UpdateCommand when passed DataRow collection with modified rows." I include a pic of the code and error.
I have a form in vb8 that is set up as follows: I have a table in my Access database calledUsers that has a name and a password (encrypted). Using the toolbar I created aBindingSource with a name of UsersBindingSource and a dataSource ofUsers Using the toolbar I created aDataset called with a Name and a DatasetName called Users_Dataset Using the toolbar I created atableAdapter called UsersTableAdapter I added two textboxes on the form and changed theirDatabindings...Text property to the corresponding field in the Database.
How to now update the database when I click Update. What the program needs to do first is encrypt the Password before saving it. I wrote the code in the TextBox2.Lostfocus event to encrypt the data a place it back into the TestBox2 field. The only samples I find on the net refer to DataGridView controls (which work) but I don't want to use them. How can I get the database to accept these changes as well as changes to radio buttons or comboboxes?
new to vs2010 express trying to accomplish a simple task read records from a sql server DB table and add them to a table (different format eventually) in an access DB Sample code below seems to work ok up to the point of the data actually showing up in the access table.
On a form i have several text boxes binded to a bindingsource and including a datagridviewI have populated the textboxes with database fields successfully and the datagridview displays the correct information.I have the following code to save the information to the database but i cannot get it to work. [code] I have tried many code examples here in order to save the data, none of which has worked.Can anyone please help me with this?
I have a datagridview that was bound using the wizard and all the column created that way. So I haven't done any code to bind the datagridview. It will pull the data from the database and dataset just fine. My problem is when I create a new row it won't update the dataset or database. I have tried different ways that I thought it would work in the code and still haven't found a usable way to do it yet. Or if I need to do all my binding and columns through code give me an idea where to start if I have to go that route. This is my first experiences with Datagridview. I normally use comboboxes and textboxes to write to a dataset and database which all work very well.
The dataGridView data source is the dgvTableAdapter with this sql statement
SELECT membres.ID, membres.refere_par, bands.titre, membres_1.prenom & ' ' & membres_1.nom AS reference_nom FROM ((bands INNER JOIN membres ON bands.ID = membres.[band]) INNER JOIN membres membres_1 ON membres.refere_par = membres_1.ID)
[Code]....
I know the delete statement works because I saw the changes in the database. If I close the form and reopen it, the dataGridView is up to date.
i'm using vb 2008 express editor, and 3.5 compact sql, through my program, i make changes, like altering rows, deleting or adding new rows, to a dataset. i want, that when button 1 is pressed, all changes made to that dataset, are updated to my database. what is the line of code that does this? [Code]
I am having the same problem <as this >> when i update my record in Access Database. It is successfully updated the record in the database. but the dataset in my project is still not updated. I am using vb 2005 to develop the application.
How to update combobox values coming from a dataset if I change the connection string. The connection string takes effect but doesn't update the dataset tied to the combobox.
I must modify 2 columns in this dataset, based on a custom function value (a normal vb function), which parameter is an another column from the dataset.[code]...
I am developing an application which uses a database that holds the information about a company and it's personnel. but when I try to edit already existing data in the dataset it just won't update it. I've tried all the method the MS sites provided me, but it just won't. the code looks like this: (notice this code wasn't complete)
AddNodesTableRows As SampleDatabaseDataSet.NodesRow Dim i As Integer For i = 0 To 10 AddNodesTableRows = SampleDatabaseDataSet.Nodes.NewNodesRow()
[code]....
End Try I've get no errors or exceptions from this code but it will not put the data into the database file. It always run through the "update successfull" yet nothing is ever written out to the file.
I have a VS2010 VB application using a SQL Server 2008 R2 database. I display a record in a form and allow the user to update the record and save the changes. However, the changes don't make it to the table. Here's the sample code for the Save button click[code]...
