DB/Reporting :: OleDataAdapter With Parameters Finds 1 Of 3 Matching Records
Apr 15, 2008
I am using Windows XP and Visual Studio 2003 .NET in VB.
I have created a parameter query using data controls on a form. The SQL works when I paste it into MS Access (and set the values to those I type in the input form) it returns 3 records. In the VB form I only ever get the first matching record. By changing the input by sorting in different orders I still only get the first matching record ( a different one). If I alter my input so the first does not match but the second and third do match I get only the second. Why Don't I get the set of three?
<Code>
Part SQL:
'WHERE
' (Houses4Sale.HousesAskingPrice <= ?)
Below is the code snippet where i would like to display a msgbox if there are no matching records. I always get a NullReferenceException at iRows = ds.Tables
I have a VB2008 Windows Form with a SDF database. The database contains two tables. The following query returns the records in DiskInfo that have a matching DiskNumber in the DataInfo table. How do I get it to return records in DiskInfo that DO NOT having a matching DIskNumber in the DataInfo table?
Dim DiskQuery = From DQ in DiskInfo join DI in DataInfo on DQ.DiskNumber equals DI.DiskNumber Order By DQ.DiskNumber select DQ
am using sql 2005 and vb 2008.i need to compare dates and select matching records betweem a selected date range.say records between 11/13/2010 and 11/20/2010.e.thing is working ok except when it comes to selecting dates between 11/1/2010 and 11/9/2010.this is happening because when am retrieving the dates from database,its being retrieved in the format 11/01/2010 instead of 11/1/2010 and so it reports no records found,and knowing the limits of sql 2005 this is the only way i can retrieve the date. [code]
I have a connection to a MS SQL database, which I understand is capable of handling multiple SQL statements in one Execution, ie
Code: Using cmdExe As New System.Data.SqlClient.SqlCommand sSQL = "Delete * from mytable where UniqueID=123;Insert into mytable (UniqueID, Field) values (123, 'something')" cmdExe.CommandText = strSingleSQLLine cmdExe.ExecuteNonQuery() End Using
will delete from "mytable" and insert a new record all at once. This is great, but I want to expand upon that to use parameters because using string concatenation in my SQL queries is a bad idea. Now my question is this. If I add a parameter which is used in multiple SQL statements, do I have to add the parameter VALUE twice to the command object? ie, will the following code work?
Code: Using cmdExe As New System.Data.SqlClient.SqlCommand sSQL = "Delete * from mytable where UniqueID=@uniqueID;Insert into mytable (UniqueID, Field) values (@uniqueID, 'something')" cmdExe.Parameters.AddWithValue("@uniqueID", 123)
[code]....
There are two questions here actually...can I add the parameters before setting the command text, and do I have to add the same parameter over and over again?
I'm getting this error, Update error: No value given for one or more required parameters, which seems to indicate a variable is not making it to Access or is empty. My procedure is meant to update a product record in the database.
Code: Private Sub btnChange_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnChange.Click Dim cmdOrderEntry As OleDb.OleDbCommand Dim strSQL As String
Currently working on a web-service with Oracle10g as back-end. Here is my problem.
1. The table I need to populate has 100 columns. I have no control over the design of the table.
2. I wanted to use the "deriveparameters" method of OracleCommandBuilder, but found out that this is "costly" in terms of performance. What I initially planned to do was to derive the parameters from an open connection, close the connection, then maybe cache the parameters obtained but I don't know if this is possible.
I am unsure how big of a hit the performance will get if I continue using the "deriveparameters" method WITHOUT caching the parameters driven. The environment is as follows
-intranet -around 2000 users -users spread out in different parts of the country
I am not familiar where they will put the web pages of the application, the web service and the database. I don't know if they'll be putting it in different servers or on one server, but that's something we cannot control too, that's why I am looking for the best approach.
I just don't want to hard-code all that parameters and if, for instance, we need to change some properties/parameters, it will be a pain to maintain the code. It would be nice if someone here can point a way to automate the whole thing w/o the performance of the system taking a hit.
I am basically trying to create some records using Structures as you can see below, however the value of Index doesnt seem to be incrementing as I am assigning it to txtCustomerId.text each time form loads, however the value of the text box remains at 1000 all the time
Code:
Public Class Form1 Dim NumberOfCustomers As Integer Dim Index As Integer
I am a high school student and i am teaching myself VB, C# and C++... it is a slow process containing mainly trial and error, looking up things online, and when the time is right asking assistance from people who know more then I.
I am currently creating a VB program that creates a database of questions, and the same or separate database. using them questions it can initiate a quiz that will save results in a different database for each student. I am having difficulties getting the code right for reading the databases, and getting it to move to the next portion of the database for each question... a little more info:
Question # = Primary key (there will not be more then 1 of the same # problem) Question Type = i am using different integers right now to specify if the question is a T/F, Multiple Choice, Open info Et Cetra.... Question Answer = Correct answer Alt answer (x3) = option to add other answers for multiple choice problems...
I don't know exactly how to get it to read a problem and when clicking a next button on a form to have it go to the next question in the database..
Is it possible to have a quick and easy way of retrieving the last 10 records from a table?
Currently what I have been doing is retrieving all the records then one-by-one cylcing through each record until I have the last 10. To me this seems to have a lot of over-head reading each record. I just wondered if there was a quicker way of doing it.
I have a DataGridView bound to a non-SQL Server database.I need to allow users to edit existing records but under certain circumstances I need to intercept the edit and instead of committing and updating the dataset I need to delete the edited record and re-add it as a new record.I have tried using every event I can think of to do this but haven't managed to get it right. [code] This almost works but sometimes completely messes up and re-adds rows twice and all kinds of other bad side effects.
An order can have many OrderDetails, and a Product can be on many different orders. The OrderDetail table just has the OrderID and productID, so there is essentially a many-to-many between order and product).I have a form for the user to enter a new order. I want to have an unbound box that contains the names of all the products, and to be able to drag these names into a box under the order, to add a new OrderDetail record using the productID of the dragged order along with our orderID.
I'm trying to build a new customer data entry page for a db project. One of the features I would like to add is a way to check and see if there have been any new records that have been added that haven't been explicitly saved to the db. If so, when the form_closing events fires I want to evaluate whether or not new entries have been made that weren't saved, and then count the number of rows that haven't been saved.
I'm using Visual Basic 2005 and I have created a program to display, edit, and create insurance records. Right now I am using an access database and it is hosted locally. What I want to be able to do is host it on our server here at our office and have the program installed on every computer on the network.
My connection string at the moment looks like this: Code: Public con As New OleDb.OleDbConnection con.ConnectionString = "PROVIDER=Microsoft.Jet.OLEDB.4.0;Data Source = C:Insurance ProgramInsurances.mdb" 'Opens connection con.Open()
I created a project in VB.Net 2008. i use a code to Add,Update and Delete record. It works fine. The problem is: How to get current records informations when i click in gridview or listview value.
I've got a large and complex database system that is about to get even more complex, and I'm having trouble coming up with a reasonable way to model the new requirements so as to minimize the performance hit.For simplicity's sake, I'm going to use the example of certification exams, although it's not a perfect analogy for my system. So we have the following tables:
- Person - Certification - Exam - Certification_Exams (join table indicating which exams are required per cert) - Person_Exams (join table indicating which exams a person has taken)
Given that model, we can easily show that Certification A requires Exam 1, and Certification B requires Exam 2 and Exam 3.We can also determine whether a person is certified by checking Person_Exams to see if they have passed all exams required for the certification we're querying. (Note that we are not directly storing certifications for a person; these must be derived. That's one of the areas where the cert exam analogy doesn't quite match my real-life scenario, so please accept that there's a good business reason for it.In my world, the cert requirements are going to change frequently, so a person might get suddenly "un-certified.")Now enter the new requirement: We now need to be able to indicate that Certification A could be satisfied by either Exam 1 or Exam 4.And furthermore, Certification B always requires Exam 2 but also requires either Exam 3 or the combination of Exams 5, 6, and 7.I've come up with a couple different approaches so far, but the subsequent queries to be able to tell whether someone meets the criteria for a given certification are then incredibly complex.
I have an input parameter for my stored Proc, Instead of choosing available values from a drop Dwn, the customer wants an empty input box that when left blank returns all records. the parameter type is numeric(6,0) in the Db. I have not found a way to leave the input blank and retrieve all records. my default value for all records is '-99' and also is declared as the default value for the param in the proc.
After a stage i have found that there are lots of codes redundancy and reusement on my disk drive. And i have also noticed that for special operation i am using the similar algorithms again and again. So i thought that if there were a program that can find the functions from specific file types producing the output of the function list etc?
I have made several posts on here lately regarding master/detail or parent/child data setups but no one has been able to help. It seems like a subject people don't like to tackle BUT I really need help.
I'm having a real hard with the DataView.RowFilter functionality and it is driving me insane.
For the most part, I have the basic master/detail functionality working. When you select a record in the first grid, it shows the correct data in the second grid. When you enter a record in the first grid, you can enter related data in the second grid. I accomplish this by using a dataview and row filter bound to the 2nd grid. When you change the record in the first grid, the rowfilter for the 2nd grid is restated and reapplied.
The problem arises when I overwrite the primary field value in the first grid and the detail records become orphaned. You would think all I have to do is change the ID in the 2nd grid to match the new ID in the 1st grid but this is where I am having problems. I wrote a loop to change the ID of each record currently loaded in the 2nd grid to match the newly changed ID in the first grid. The code is here:
Code: Dim I As Integer
For I = AuthorizationGroupsDGV.Rows.Count - 2 To 0 Step -1 AuthorizationGroupsDGV.Rows(I).Cells(0).Value = StrEmployeeID Next
I have used this code before and it works great. It has to step backwards through the grid because when the ID's are changed, they no longer match the RowFilter criteria and they disappear from the grid. They still exist in the dataset. The problem is, while the code "works" the intended effect does not. Some of the records completely disappear from the dataset and do not reload when I restate the row filter against the new ID number.
Is there a program where i can launch a website, click on a button or textfield and it will give me the getElementByID? I searched around for this and i have found nothing? Why doesn't this exist? I am writing a program that will enter information into a copiers web interface for scanning. The problem is the copier's web interface uses Java and XML. I cannot get my program to enter the information into the apprioate field because i cant find the tag to reference it! its very annoying, this is the last stage to my program.
So I have been assigned to create a program that finds prime numbers. And then for the final part of the program I need to have the computer find the millionth prime.
I'm creating an application that finds all of the text in a picture regardless of text size or font (whithin reason, Just the basic monospaced and default windows fonts). I tried making my own but it was slow and very unreliable. I need it to work fast (as close to instant (give or take 1 or 2 seconds)). I have to run it on images 1000+x1000+ (Nothing more than 1500). I have to take the values of the text and the position of it in the image.
The sub below will show all of the directories contain with a directory
Code: Private Sub showDirectories(ByVal rootDirectory As String) Dim rootDirectories() As String = IO.Directory.GetDirectories(rootDirectory)
[code]....
When I run this code I can use any directory as the root directory except My Documents.When I use the directory path with My Documents, as well as finding all of the folders contained in My Documents, it finds three extra: My Music, My Pictures and My Videos. Those three folders do not exist at all in My Documents. I have checked hidden files and folder and they are definately not there yet the showDirectories() sub says that they are.The exact error is: Access to the path 'C:UsersMichaelDocumentsMy Music' is denied.It's dened because the folder doesn't exist. I have checked myself using Windows Explorer!Despite this, when I type 'file:///C:/Users/Michael/Documents/' in the address bar of Google Chrome, it shows all of the files and folders in My Documents and, guess what, it shows the folders My Music, My Pictures and My Videos. But Windows Explorer doesn't show these! The strange thing is, for each of the folders, the last Date Modified was 23/01/2011 13:42:49 exactly. Each of the folders was last modified at that exact second simultaneously!I have 3 "ghost" folders "haunting" my My Documents. Is there any programs out there that perform "exorcisms" cause I am seriously freaked out!Perhaps this is the wrong place to post this. When I started writing this thread, it was about Visual Basic but now I realise it has nothing to do with programming at all.
Public Class form1 Inherits System.Windows.Forms.Form Private Sub cmdCalc_Click(ByVal eventSender As System.Object, ByVal eventArgs As System.EventArgs) Handles
[CODE]..........
This is my code for solving the quadratic equation..you input an a,b and c value and it finds the roots but i dont know how to graph it.
