DB/Reporting :: Use DataSet For Local Data Storage?
Mar 22, 2009
I need a simple method for a user to enter as many rows of data as they wish (probably won't exceed 50 in most cases and that's pushing it) and then store that data for retrieving the next time they want to reuse that list. I will also need to read the rows in for manipulating text in a file with those entries.
Would the best method to be to use the DataSet in VB Express 2008 and then use the DataGridView for allowing the display and entry of the data?
View 1 Replies
ADVERTISEMENT
Jun 10, 2009
say you have a database that you want to store 100 different recipes in. Out of that 100 recipes 20 have 5 ingredients, 30 have 7 ingredients, 30 have 4 ingredients and 20 have 6 ingredients. So what's the best practice for storing an unknown number of items in a database?
Currently what I am doing in these situations is storing them in a single field in a database separated by a comma. Then when I have to retrieve them I split them by the comma into an array. This doesn't seem right to me but I haven't noticed an impact on speed or efficiency, so what would be the best practice to handle this situation?
View 2 Replies
May 12, 2008
I am quite green to VB .NET and it start occuring to me that I am doing things probably in a very ineffective way.Anyway here is the problem I have datasets, consisting of integers there is set 1 which is of format ID, ID2 - ID here is unique but different ID can refer to same ID2. Before I start reading in the data I have unknown number of these entries (ID and ID2 can be at least as high as 99999999)
Then I have a second data set of format ID2 here is the same as in the set 1 and it can contain several PID entries (all integers). In this set the ID2 is unique and again for one ID2 there can be unknown amount of these PIDs, same PID can occur more than once.
[Code]...
View 17 Replies
Aug 3, 2010
I recently changed a For Each loop to a Parallel.ForEach loop. I'm concerned about an object being declared outside the loop but assigned while iterating in the loop. Here is the simplified code.
Dim results As ModelResults
Dim noResultsModel As New List(Of ModelResults)
Dim lock As New Object
Parallel.ForEach(_modelEngines,
Sub(model)
[Code]...
Is there a potential race condition with the results object? Would anything be different if I moved the declaration of results into the for loop?
View 1 Replies
Jan 6, 2012
I want to resize the resolution of an image before uploading it to local storage. Right now it saves the image in its full resolution and I have to manually resize it using width="200" height="200" or a css tag in aspx. I want to reduce the file size of an image before storing it, hence by resizing the image resolution when the user uploads it via button. I've tried using System.Drawing before and setting the int imageHeight and int maxWidth to be resized but couldn't seem to get it to work.
My code so far is:
Protected Sub btn_SavePic_Click(ByVal sender As Object, ByVal e As EventArgs) Handles btn_SavePic.Click
Dim newFileName As String
Dim SqlString As String
[Code] .....
View 1 Replies
Nov 10, 2011
I've been reading a lot of articles here and there, really, for the past two days, searching for a good local storage system. I have no immediate use for now, so I am just exploring my choices. By saying 'local storage system,' I'm talking about some sort of database used for applications that let users manage and organize personal accounts (bank accounts, web site accounts, application licenses...). I do use XML to store user settings. But if you have to manage lots of information locally, XML won't probably be good enough, I'm afraid.
So what are choices Visua Basic users? Well, as I often mention, I develop Mac software products. And I use SQLite. In fact, every one of some 40 apps sold at Mac App Store uses SQLite for good reasons. I know that you can use SQLite with Visual Studio after installing a package from sqlite.phxsoftware.com. But I don't know if your application can reproduce a database file when necessary. That being said, I'm looking for a system that I can use to create a file programmatically especially when the user launches it for the first time. So what do you use to locally manage large information? SQL Express? SQLite? XML?
View 10 Replies
Mar 12, 2009
I'm writing an application to mimic a cash machine, I have a Form1 on which the user enters their PIN and chooses their card no. from a drop down box.The accountID is passed to Form2 and I know this is successfully seen by displaying it in a simple message box.A data adapter and dataset are used for this to the cards table.However, what I then require is within Form2 to retrieve the balance from that accountID in table Accounts, another data adapter and dataset have been created for this under Form2.I'm trying to get the balance into another variable, and I have written this as follows: [code]I would expect the result of this to be e.g. 100.00 but instead I am getting a response of "There is no row at position 0".
View 1 Replies
May 18, 2008
I have a storedProcedure that populates a dataset, this dataset is then used for a dataSource for a third party grid control. This all works fine, however I am having real trouble in updating the dataSet with the most recent data from my database.Below is the code that I am using to populate the dataSet:
[code]...
I am not sure how to update the dataSet with new data so that my grid control displays the most recent data. Could someone show me the code to do this?
View 3 Replies
Oct 15, 2008
is my code in VS 2008 (VB) to show Crystal Report. but crystal show saved data not my dataset:[code]
View 4 Replies
Aug 22, 2010
Only my local dataset updates when adding, deleting or editing records.The Source Database is supposed to update on issuing DataAdapter. Update(dataset )However, when I check my source database after running the operations it remains the same as the original.
View 6 Replies
Jan 9, 2009
I want to do something like this:
Code:
'create a dataset and a table
Dim ds As New DataSet
[code].....
View 5 Replies
Aug 15, 2011
I don't know how to join multiple datatables created in Designer in 1 single Datatable. I need 1 Datatable with all data in it so I can give that single Datatable to one single Tablix in ReportViewer (rdlc). Problem: ReportViewer Tablix can accept only one datatable at time and I need them all at once in one tablix.
How did I get stuck here:* I have added Dataset from Solution Explorer to my Project (ds1). Double click on that item gave me Dataset Designer (ds1.xsd). Here I have created 4 Datatables with all needed columns, mutually connected with parent-child relationships (one to many, nested). dt1 is parent to dt2, dt2 is parent to dt3, dt3 is parent to dt4 (dt1 > dt2 > dt3 > dt4).
On my forms I have binded all my controls to this 4 Datatables and their respective columns so the data is populated hierarchically to dataset (as planed). I have added ReportViewer Control to one form for reporting purposes and Design a new report (rdlc)...As I have read in past few days (read: week or two) I need to Join all my datatables to one single (flated) datatable somehow and then feed that DataTable to my Report.
So basically I have 2 questions: 1. How to join my 4 datatables? Can I do it from Designer or I must do it in code? 2. If I cant do joining from Designer how will I see this new datatable with all columns from my Report? If I wanna add a Dataset/DataTable to my Report I go to Tab Report Data - New - Dataset - comboTo SelectExistingDatasets and if Datatable/Dataset is not created in Designer I can not see it here to add it to work with it.
View 7 Replies
Jan 26, 2012
I'm a junior VB programmer and looking for some advice on this subject. I'm trying to create a chunk of code that will create dynamic storage for variables for use later by dynamic custom controls.
For example:
An INI file might have an entry in it that looks something this:
....
[var1] <-- this becomes the Storage name
description=My Variable
type=System.Int32 <-- this could be any valid VB type
last_val=456 <-- Other code would save the last value
....
And I want to access the data using a standard "property set" like so after it's created:
var1_reference.value = 55
I've tried using a generic class which works ok as long as I declare the variables at design time from within the design environment. But when I try to create them from the INI file it gets messy.
Here's the simple generic class i've constructed to test this:
Public Class GenericVar(Of T)
'
' Generic Symbol Class for data storage
'
Private VarName As String
Private VarType As Type
[Code] .....
Also, as each object is created (and they could be different types) I store a reference in an array to make it easier to keep track of, but I'm having a hard time getting access to the objects and their properties, and certainly cant seem to assign an event handler to it once its in an arraylist because the design time code doesn't know what "Type" it is in the arraylist of objects.
View 2 Replies
Dec 2, 2011
Where should I store my programs user data so no one will have trouble accessing it?
View 2 Replies
Oct 19, 2009
I have and application written that works great on XP. It is VB.Net 2008, using .net 3.5. I install and Access database to the program file directory. In Vista, I get an error that is permissions related as even admins don't have default write permissions to the Program Files directory and access creates a .ldb file when in use. To solve this, I have had the users give themselves permission to the folder.
Is that the best solution? If not, where should data be stored in Vista and in Windows 7? Also, I have an update feature of my software that will download updates to the program files folder. Is this out, too?
View 20 Replies
Mar 4, 2011
Whether using XML database for data storage is safe enough? because I wanted to branch using an XML database and then she sends the data to the center. and then the data is in process at the center and then incorporated into the database server
View 4 Replies
Jun 9, 2009
I have finished my program and now i am ready to deploy it. The only problem is it is a multi-user application. All i want to do is simply run the program with the database from a server, and have other local computers with the program access this same database. I know that you have to change the connection strings for the local computers, but how can i go along doing this?
View 2 Replies
Jul 18, 2008
My boss wants me to create local databases on the light-side of things. I was researching on what solutions are available, we discussed the possibility of using text or xml files... but we dropped the idea since we want to use SELECT, UPDATE, DELETE command sets (or the like)I proposed the idea of using Access files (mdb) but he told me that he doesn't want the user to have Access installed on their computers.What are the choices avaible, am I forced to install Access on machines that would be using my VB .NET app to access mdb files?
View 2 Replies
Apr 13, 2009
I have created a local database using the DB wizard in 2008 express.I have created a table called users and I can access the sample data that I have entered into it using a windows form.When I try to add a new record things come unstuck. The record shows in the windws form as being present and the record count increases to indicate this. But when i check the DB itself there is no sign of the record.I am using the tableadapter method as outlined by MSDN. So the question is what am i doing wronghere is the code from the form:
Public Class frmS4
Private Sub UsersBindingNavigatorSaveItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles UsersBindingNavigatorSaveItem.Click
[code].....
View 6 Replies
Jun 5, 2010
I'm relatively new to the vb.net framework and object oriented programming. After perusing the threads for a few hours I can't quite find an answer so I'm posting this thread. I'm not necessarily looking for code examples. I just want to know if it's possible and where to look next. Basically I'm trying to build a starter application that will help me learn programming. One of the main things I want to do is to be able to dynamically (at run time) create a set of information (data) that can be manipulated via a set of static (and/or dynamic) functions/calculations. The reason I need it to be dynamic is because even though this program is really just for my own fun and perusal on my own machine (and I want it to be able to run without any outside connections (i.e. databases or servers) the data itself is going to be location (i.e.State of residence or even city) specific. Essentially most of the data will be numerical and can be of the integer type. But I'd like to be able to adjust and create new data sets if desired. From everything I've read and researched I haven't found a way to do this (at least now without an excessive amount of coding that is above my expertise). So I want to know if there is a way to do this that is relatively simple.
View 2 Replies
Apr 13, 2011
I do not know much of datasets. I have created a local database with a table as per img 1 attached, and I use them in a simple drop down selector as per img 2. But I get the message as per img 3 , and I played around with the dataset, removing teh primarkey, etc.
View 2 Replies
Mar 3, 2012
I'm just getting started with Visual Studio (2005), and my aim is to write a fairly simple application in Visual Basic that will need to store some data to disk.What I really want is to be able to send the application to the end users (xp, vista, win7) and have them just be able to use it without having down download all kinds of extras. For example I'm guessing that if I use an SQL database in my application they will need to download SQl server express or some other sql downloadable?
If so is there a similar downloadable for MS Access?I'm just in the 'seeing how things work' stage at the moment and I don't want to waste time going down the SQL track just to find it won't actually work unless my users all download SQL to their machines (which they won't want to do).
View 4 Replies
Feb 22, 2010
I am trying to develop a report that displays the result of a query that returns two tables. The first table is always a single row of values, the second should be a grid. I can get a report to display either independently, however it will not allow me put them both on the same report.
View 1 Replies
Jun 2, 2011
I have a dataset that I'm trying to loop through to be able to save any changes made to that dataset and update my database doing so. Is that possible? I've seen that it's possible to do it with datatables but not datasets. If so, can someone offer a starting point for me to learn with?
View 1 Replies
Nov 18, 2008
What is the best place (event/procedure) to use the newest record when navigating from record to record on a form.
For example, I want to do a calculation on 2 text boxes that are bound to a dataset. This calculation will be done each time a new record is navigated to.
View 1 Replies
May 12, 2010
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 .
View 1 Replies
May 23, 2009
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]
View 1 Replies
Jun 4, 2012
I am using VS 2008, VB.NET and Windows XP r3.I am trying to use LINQ to DataSet in my app. In my test app, I can get it to work find. My test form has an OleDbDataAdapter, an OleDbConnection and a DataSet. It also has a DataGridView bound to the one table in the DataSet, a BindingSource and a Button.[code]
View 7 Replies
Mar 5, 2009
I'm having a problem with a database. I"m using these two functions to add and remove folders to the database:
Code:
Private Sub AddToFoldersTable(ByVal AddFolder As String)
If FoldersBindingSource.Find("Folderpath", AddFolder) = -1 Then
[code]......
View 1 Replies
Apr 25, 2011
Here is my code that parses an XML string to a datagridview:
Dim DS As New DataSet
DS.ReadXml(New StringReader(StringHTML))
DataGridView.DataSource = DS
[code]....
Child list for field Produits cannot be created.I'm sure it's something so simple you guys are chuckling...Can't wait to see what's the problem
View 10 Replies