Dataset Showing As Empty?
Mar 10, 2011Public Class ReceiptEntry
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Ado.net - Checking If Dataset Is Empty
Apr 2, 2011How do i check if the dataset is empty? I wrote the following code:
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Check Empty Dataset
Oct 4, 2011i have a dataset that takes results from a select to a sql database. the select returns rows and sometimes returns no rows. how can i check if the dataset has no rows from the select? [Code]
View 4 RepliesTell If A DataSet Or DataRow Is Empty?
Feb 23, 2012After much convincing by other people, I have finally started trying to use ADO.NET instead of ADODB. Unfortunately, my lack of knowledge regarding these objects has left me broken in one area. I tried converting the area where I am checking for duplicate records to use ADO.NET by checking if a student filling out a form enters the same first name, last name, and program or major as another record in the database as per my instructions. Unfortunately, in the following code snippet, it is not behaving how I thought it should and I am unable to diagnose exactly where the problem might be just yet.
Here is the code in question:
Try
Dim orion As New SqlConnection(strConn)
Dim sqlCmd As System.Data.SqlClient.SqlCommand = New System.Data.SqlClient.SqlCommand(query, orion)
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I probably should have mentioned also that it never flags an error despite there being 'duplicate' records in the database at this point.
Check Whether Image At Dataset Is Empty Or Not
Feb 14, 2009im getting a image from my database to a data set. before i convert it to a proper picture i need to check whether ds.Tables("userDetails").Rows(0).Item("photo") is EMPTY or NOT. How should i write the if condition? <code>If ds.Tables("userDetails").Rows(0).Item("photo")<> ??? Then
Dim pictureData As Byte() = DirectCast(ds.Tables("userDetails").Rows(0).Item("photo"), Byte())
Dim picture As Image = Nothing
Using stream As New IO.MemoryStream(pictureData)
picture = Image.FromStream(stream)
End Using
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Dataset Rows Count Empty, But Table Is Not?
Apr 8, 2010MsgBox(MyDataSet.mytable.Rows.Count)
Gives 0, why?
The table has data!
Fill Empty Access Table From Dataset?
Jun 3, 2011I think this may be a usual issue but I am not able to find much info. There is a master customer database and a call log database at work. The call log database has two tables that are updated from the master database monthly. Now I am writing this vb frontend for the call log database and cannot figure out the update portion
For p = 0 To maxrowsC (currently around 1000 rows)
With myCommand.Parameters
.AddWithValue("@HEATSeq", dsCallLog.Tables("ConfigDS").Rows(p).Item(0))
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VS 2010 : Empty Dataset Conversion To Table?
Jan 13, 2012I inherited a program that retrieves 3 datasets from our vendors' web services, converts it to a table and then merges the 3 tables before exporting into xml from the resulting combined table. The problem I am having is that when web services returns an empty dataset the program crashes in the attempt to create a table from the empty dataset.How do I modify this code to either create an empty table or recognize the empty dataset and skip around that particular table creation, merge and removal? There is always data in at least one of the datasets.
foreach (Branch branch in branches)
{
Console.WriteLine("Opening connection...");
Vendor.ws_ordersSoapClient VendorClient = new VendorInterface.Vendor.ws_ordersSoapClient();
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Dataset Not Showing Changes To Database Table
Jan 29, 2012Using Visual Basic 2010 Express on Windows 7 whilst learning to program a database application using windows forms. I created a database (.mdf I think) with a tables e.g. patient details. Then created a form and dragged dataset and database adapter follwed by dragging database fields - this all worked perfectly well. I then created a table "tblSuburbs" with key suburbID, suburb, postcode fields. This also went well when creating a form to add, modify or delete suburbs. I modified my Patient table to include a link to the Suburb table - creating a relationship and saving both tables. Here comes my problem - Whilst the Database Explorer shows the "_SuburbID" field I added to my patient table, it does not show up in the DataSet even after I try and "refresh" every "refresh" button I can find. I need the DataSet to show the link field as I need the User to select which Suburb they in.
View 4 RepliesShowing Current Record Of Dataset In Datagrid?
Mar 11, 2010I m working on vb.net ado.net oledb, I have also added datagrid Control to my form
for retriving database from .Mdb file i used following code
'decleared Name Space
Imports System.Data.OleDb
'Dicleared Variabls in Class Form1
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how to move current record in datagrid, i mean when i press Next record button then datagrid's data (table) also should move to next record or when i click any record in datagrid, then the current record of dataset also should move to clicked record of datagrid, so that i also may see datagrid's clicked record in textboxes in short i want to use default feature of vb6's ado control, when we bind datagrid with ado control, it worked autometically, both data grid and adodc wer connected each other at a time, so that moving next record also apears in datagrid.
Form With Crystal Report Viewer Not Showing DataSet
Jul 19, 2011Imports System.Data
Imports System.Data.SqlClient
Imports System.Text
Imports CrystalDecisions.CrystalReports.Engine
Imports CrystalDecisions.Shared
Imports CrystalDecisions.ReportSource
[Code] .....
When I run this code my form with crystalreportviewer not show dataset
Dataset Bound Datagridview Not Showing Latest Data From Database
Jun 5, 2011I am creating one application visual basic and sqlce.I have two forms name Form1 and Form2.
I used Form1 to add data to database using OLeDb command and used Form2 to show data in datagridview by using dataset[code]....
VB Express 2008 Dataset Not Showing New Database Objects (views)
Mar 3, 2010I am using VB Exopress 2008 and SQl Server Express 2008 in Windows Vista Home Premium. I have created a dataset after importing all tables and queries from MS Access to SQL Server. I have now added a view in SQL Server that I want to access and use in VB Express. However on clicking "Refresh" for the dataset the new view does not display in the available objects, only those I originally imported and opened with the original dataset. What, pleas am I doing wrong? How can I see this new View?
View 3 RepliesClear Dataset But Get Error Sometimes If It Is Empty When Try To Clear It?
May 17, 2009I have a timer that runs every time by itself, and for the code the runs in it I would like to have it clear the dataset before it does anything, the timer runs every 10 seconds, so I tried to do dataset.clear but it would crash if the dataset had no values
View 4 RepliesWhy Is Model Only Showing One Make Of Car / Yet Cars Is Showing Full Lest
Mar 31, 2011I have a problem with the combox its only displaying the first item in the list its being populated by a webserice call the drop down in question is comboboxmodel now the manufacture one is fine and sets as it should any reason as to why the comboboxmodel would not. [code]
View 1 RepliesDataGridView - Convert Nulls To Empty Strings And Display It In The Grid As Empty Strings
May 14, 2009I have a DataGridView that has some columns with dates. It binds to an in-memory Datatable which gets loaded from an string array of data passed back from the backend Some of the rows returned have nulls for the date columns. Solution 1: If I define the Date column in the DataTable as "string" I can easily convert those nulls to empty strings and display it in the grid as empty strings (desired results). However, if the user clicks on the date column header to sort by date, it doesn't order the rows as you want. You get a purely string sort order. Not acceptable
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Nothing Equals String.Empty, Null Does Not Equal String.Empty?
Jun 28, 2010This must've have been asked before but I couldn't locate it. In a mixed code project (VB and C#) we were debugging some old Visual Basic code where a statement as follows could be found:
If Request.Params("xxx") <> "" Then
'do something
I considered this a bug as Request.Params could be null, in which case the statement would've become false which wasn't the idea. So I thought. I just found out, -- probably for the tenth time and I will keep forgetting -- that the following two statements are not equal, while Nothing in VB should be equal to null in C# (thought I):
if(String.Empty == null) // always false
If String.Empty = Nothing Then ' always true
Should I dismiss this as a typical Microsoft backward compatibility effort, or should I consider this a huge error in the VB.NET compiler? Does anybody know the Microsoftean opinion on this oddity?
Arrays - If Not String.Empty Ignoring Empty String
Aug 11, 2010I have a array of strings and I am looping through them, but the string might be empty so I am trying this:
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DataSet Editor - Allows The User To Edit A DataTable In A Strongly-typed DataSet
Mar 15, 2010When the user clicks an "Edit" button on my form, I want a box to come up which allows the user to edit a DataTable in a strongly-typed DataSet. What's the best way to do this?
View 2 RepliesIDE :: Dataset Code Behind Datatable.ColumnChanging Event Firing / But Dataset.HasChanges Property Not True
Jan 28, 2010I have code running in the Datatable.ColumnChanging event in my dataset. This dataset underlies a form and conventional drag/drop controls are in place for data entry.when the event triggers and runs, I am running code in the form that checks the dataset.HasChanges property. It is showing False. But this is immediately after the ColumnChanging event has been triggered.Okay, I see by others posts and MSDN that .HasChanges will only be true after moving off the row with the changed column. I have also noted lots of discussion about the advanced binding property of DataSourceUpdate Mode, but that does not address this issue.I guess I can do this by checking the state of the row for the binding source. Just seems odd that the event behind the dataset can be triggered and that does not change the dataset.HasChanges property.
View 3 RepliesSystem.Data.Common.DbDataAdapter.Fill(DataSet DataSet)
May 14, 2012I have tried everything I can to get beyond this error which shows below as <<<<< error here. It is trying to fill a dataset from a data adapter. If I change the SELECT statement to just SELECT * FROM xTable I get the correct number of records in each table. But anytime I try with a more complex statement I get the error message shown below which indicates System.Data.Common.DbDataAdapter.Fill(DataSet dataSet. I've completely erased all data and entered a new set of test data so I know there is no problem with relationships. Each table has primary key which is foreign key in other table. IS there something wrong with the Imports section: Imports System
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.net - Copy Data From Dataset To A Type Dataset Using Automapper?
Aug 24, 2010i am trying to copy data from a standard Dataset to a Type Dataset (XSD) of same table structure. i want to use Automapper to do that one. So how can i do that using automapper?
View 1 RepliesFill A DataSet On Application Startup And Use Dataset Other Form?
Jun 5, 2010I need to pick all data in my application from my database and use it in my form
my question : how to pick all data in my application then i use it
Loop Through Dataset Updating Data From Results Of Another Dataset
Jun 22, 2010I have two Datagrids, One grid has all the customers garments on it with style number and contact length. The other grid has the users who have garment issued to them. the style number is in both grids. I need to loop through the users grid and say if the contract number is 1 from the first grid then the contract date on the second grid will be todays date + 365 days (year contract) I have looked at using a stored procedure and also a for each command but I am just getting stuck with it all. [Code]
View 1 RepliesSaving Dataset To Database Which Has Imported Rows From Another Dataset
Jan 4, 2011I have a problem saving a dataset which contains rows that i have imported from another dataset. i can successfully view the imported rows in a gridview but i cannot commit the rows back to the database.
View 2 Replies.net - Combine Multiple Dataset Columns To One Dataset?
May 19, 2010I have multiple datasets that I would like to combine into one. There is a common ID field that can be associated to each row. Calling Merge on the dataset will add additional rows to the dataset, but I would like to combine the additional columns. There are too many fields to do this in one query and therefore would make it unmanageable. Each individual query would be able to handle ordering to ensure the data is placed in the correct row.
For Example lets say I have two queries resulting in two datasets:
SELECT ID, colA, colB
SELECT colC, colD
The resulting dataset would look like
ID colA colB colC colD
1 a b c d
2 e f g h
Repointing A Report Dataset To A Test Dataset
Feb 18, 2011ok, I've finally got my test database issues sorted out, however now I need to actually modify my existing report to add the two new fields from my test database. I have made a copy of the report so that I am not modifying the original. I have deleted the two old fields and now want to add my two new fields in there. In the Field explorer window, I see an object called "dataset1" and when I expand it, it is using a view that includes fields from the table that I added my two new fields to.
The problem I see here is that I have gone in and modified the view to include these two new fields in my test database - but again, they are not showing up as selectable fields here. I am just assuming that "dataset1" is somehow pointing to the live database again and that I need to change the datasource location.In my solution explorer, I see an object called "dataset1.xsd" but the properties of that do not tell me much about where it is actually pointing to...
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VS 2005 Typed Dataset Vs UnTyped Dataset
Nov 25, 2009I want to access data using both the datasets.
Private Sub Button3_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button3.Click
Try
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In my code i have dataset name ds and table named Info1,when i write ds after that how tablename is coming,its not possible? How to do that ?
Asp.net - Geocoding A Dataset - Map A Dataset Of Addresses On A Map
Aug 2, 2011i am looking to map a dataset of addresses on a map. basically, i want the users to type a street name in my town and be able to see the houses that have signed up already on that street. so a pinpoint should show up on the houses that came up on the dataset.
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C# - .NET Dataset Design - Have A Dataset For Each Table?
Jul 23, 2010I 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)
