The following piece of code executes a SELECT query and places the result into a textbox, but if the query returns nothing an error appears saying that there is no value and it won't continue the lines of code after it. (I modified code I found on a website after a Google search, I'm not sure if this is the best way to do it but it seems to do what I want.. so far)
[code]...
How would I change the code so that it checks the query to see if it returns a result? I'm still not too sure what the SqlDataReader can do fully, so I'm not sure if it can check for a result.
I'm querying a SQL DB and sometimes the result is Null, so I thought I would test this but my code results in an error "Data is Null. This method or property cannot be called on Null values."
Here is a snipet of my code: For i = 5 To 6 cmd = New MySqlCommand(query2t & i, db) rdr = cmd.ExecuteReader() rdr.Read() If Not IsDBNull(rdr.GetUInt32(0)) Then [Code] ......
There are some TimeSheet that have no TimeRecord, which I need to select as well. How can I select all of them to make selection like above wanted result? I'm thinking of how I can include some condtion checking in the query to see if this TimeSheet has no TimeRecord then no need to Sum(tr.BonusHour) just assign TotalHour to zero.
When Creating a query using the sear Criteria Builder . I keep getting the error : "The schema returned by the new query differs from the base query" what does that mean and how do i avoid this problem in future
I am connecting to an Access database and using a parameter query with the LIKE operator to return all rows that match query. The string to search for is taken from a Textbox
sql =
"Select * FROM Allview WHERE Info Like" & "*" & CStr(TextBox1.Text) & "*" The query does not return any data in vb, but when run from access with same string, there is data returned.The connection to the database is done correctly, as I am able to return data with various other queries.
Partial code : Dim con As New OleDb.OleDbConnection[code]....
I am trying to run a query an Access db from VB. The general query which I want to run is
SELECT * FROM Patient WHERE Patient.PatientID = ? or SELECT * FROM Patient WHERE Patient.PatientLname = ?
I tried using an input box which captured the user input and pass that variable to the query, but that failed. Then I read about writing a function and using that, however, I keep getting an error which says Function not defined, but when stepping through the code, it seems to work. Here is my function: [Code]
The database: "ID (Primary key)" | "Title" 0 | "title1"
[code].....
OK, before adding values to database, we should check if a row exists with this values :)TO do this, creating a Stored Procedure is a best way to deal with the database fastly.So... The problem now is, at the runtime, Miss OleDB throw this error:Microsoft Jet database engine cannot find the input table or query 'IF
i should say hi experts :D . Help me with this pretty code :)
The database: "ID (Primary key)" | "Title" 0 | "title1"
[code].....
OK, before adding values to database, we should check if a row exists with this values :)TO do this, creating a Stored Procedure is a best way to deal with the database fastly.So... The problem now is, at the runtime, Miss OleDB throw this error:Microsoft Jet database engine cannot find the input table or query 'IF
I have to join two main tables, and I need to filter the results by elements in an ASP.NET web form. These filters are created on the fly so I have to use a lot of where extensions to filter the query. I want to execute the query with as optimized SQL as possible.
I am first doing a simple join between TW_Sites and TW_Investigators. Then there are two sub-tables that are involved. TW_InvestigatorToArea and TW_InvestigatorToDisease. While most of the where clauses are working fine, I have found a performance issue that won't be an issue right now, but will be an issue as the table gets bigger.
The arrays DiseaseCategories and DiseaseAreas would be the results of a CheckBoxList result.
Protected Sub LoadResults() 'Get Dictionary of Filters Dim FilterDictionary As OrderedDictionary = Session.Item("InvestigatorFilterDictionary") ' Initialize LinqToSql
I created a RDCL in the designer. I would like the User to Determine what is shown in the Report. How can I change the query at runtime? (ex. changing the customer Name)
This is the query that I have in the properties:
SELECT [Date], Address, Customer, Orders FROM Report_qry WHERE (Customer= 'JohnDoe')
how to take a query that returns a single row of data and load that data into textbox controls.I know about ExecuteScalar but it is only good for a single column of data from the query.
I've got confused at the moment.I've got one database to developed for MLM (Multi level marketing) company.so, there's one Members database.. each member have unique ID called membercode.. and all members can members under them.. can make 2 members down to 1 member.. all members are added in same table named "tbMembers" and for each member there's a "parentID" where I add member's membercode under whome that member is?.. right?
Now what's the matter is .. I want a SQL Query which can go under and under.. like 'John Doe' having two members under him named 'Suzan' and 'Ellie' and 'Suzan' is also having 2 members under her.. and same for Ellie. and for example.. 'John Doe' having about 300 members in his down line? All members are making transactions.. like they purchase product and Invoices are being generated (invoices tables have 'memberID'). Now the query is how to generate query which can calculate John Doe's Downline's TurnOver from invoices table's 'totalAmount' field's SUM?
I'm using Asp.net 2.0 (VB.net) and use SQL Server 2005 Express.
When I use the Execute Query button in the Tableadapter Query Builder, the query works fine; I get all the rows I expect. However, when I run this in my code, the query behaves like an equality statement (i.e. Lotnumber = @Lotnumber) rather than a LIKE statement (Lotnumber LIKE '%' + @Lotnumber + '%').Here is the code that is not behaving correctly. Note that I have a textbox, LotSearchTextbox, where I enter the portion of the Lotnumber that I want to use as the filter. I also have a button, LotSearchButton:
Private Sub LotSearchButton_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles LotSearchButton.Click Try Dim SomeNumber As Integer = Me.LotCalcinerO2TableAdapter.FillByLotNumber(Me.CalcinerDBDataSet.LotCalcinerO2,[code].....
why the query works in the Query Builder but not in the code?
I have 7 company Divisions that sit in an access database.I then use this list to populate two comboboxes in my windows form.However I get a syntax error in my SQL Query if the Division name is more than one word.For example in my access database I have two columns one is a status column and the other is a division column. If for example the Division is called 'Corporate' the status column is called 'Status Corporate' and the division column is called 'Corporate'.The SQL query works fine in this scenario.However if I have a Division that is more than one word, lets say 'Operations Division' I get an error in my SQL Query that says -
Quote: Syntax error (missing operator) in query expression 'Operations Division'.Here is my code
sqlNewTenderDetails = "SELECT " & Me.DivisionBox.SelectedValue & " From BidRefCodes Where " & "[Status " & Me.DivisionBox.SelectedValue & "='Active'" daNewTenderDetails = New OleDb.OleDbDataAdapter(sqlNewTenderDetails, NewTenderDetailsTableCon)[code]....
I've recently been trying to figure out a way to get parameterized queries to work and i think i'm almost there but seem to be getting an error when executing my query
I want to query an access database with variable data defined by the user. The "Search" criteria would be in a textbox. I made a query like
SELECT askID, Question FROM chita WHERE (askID LIKE 'Textbox10.text%') and referring to this query as
Form1.ChitaTableAdapter.searchrec(Form1.ChitaDataSet1.chita)But id does not take the value of the textbox, instead it takes the Textbox10.text as a value. Is it possible to refer to it like this, or should I Linq?
I was wandering is it possible to use a query within another query below is the code I am trying to use.
Public Function GetInventByComp(ByVal CompID As String) Using DC As New DataClassDataContext 'need to get company id's based off names? thats bad should be name from Id need to rethink this Dim invent = (From C In DC.Inventors_Companies _ Where C.CompID = CompID _ Select C.InventorID).ToString
[Code]...
I was trying to us multiple values in a string like "1, 3, 5" but I can't seem to get that working either so I am trying to use just a single value now. Can anyone help me? "Yes I am new to this"
I am using visual studio 2010 to create a form where you can edit,delete, or insert data from an accessdatabase. When I try to run the form in a web browser I get the error "Query input must contain at least one table or query." I believe that the problem lies with my code/syntax but I am unable to determine the cause of the problem.
<asp:AccessDataSource ID="AccessDataSource1" runat="server" DataFile="~/App_Data/database.accdb" SelectCommand="SELECT * FROM [database]" DeleteCommand="DELETE FROM [database] WHERE ([EmployeeID] = @EmployeeID)"
i am writing a vb.net program which gets a c program as an input and checks it for errors,now i want my program to skip the comments in the c program,i have written some code but its not working
For Each line In TextBox1.Lines sample = TextBox1.Lines(k) Dim len As String len = sample.Length
Basically, I have a list of dates in a SQL table with some statistics next to each of them. I want to compare the dates in the table with a certain date I choose. However, my dates in my table are stored as Varchar(50) (and have to be). Apparently I can convert the date in the table into date type but I don't know. Does anyone know how? My current code can be seen below.
I have a form which contains a checkbox field. On page load I want to create a separate checkbox for each customer in my Database. The code I have to create the checkboxes for each customer works fine. However, I also want to check in the database if the customer is set to unauthorized if they are then I want to check there box. I also have code for the case where the user checks a box. If a box is checked I update the database setting the unauthorized attribute to true. My problem is when I check a box it works fine and the box is checked, however if I reload the page all the boxes are unchecked. So either my database update is not updating the database or the way I check on page load for checked boxes is incorrect. Any ideas?
Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load Dim sql As String = "SELECT Name, unauthorized, ID FROM Customer ORDER BY Name" Dim dt As DataTable = db.execDataTableQuery(sql, "Customer")
I am trying to check whether a row is getting inserted into my database. It is throwing an error even when it does insert (it's a database issue that will get resolved later when I get a newer version of Microsoft Access), so I can't check whether the insert is successful based on whether there's an error or not. I think I need to check the AffectedRows of something, but I'm not sure what. I've been looking for info on how to do this but I can't figure out how to make it work for my exact situation. Here's a general idea of what my code looks like:
Protected Sub Wizard1_FinishButtonClick(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.WizardNavigationEventArgs) Handles Wizard1.FinishButtonClick
[Code]...
But the numInserted is coming out as 0 every time even though the insert is successful. It may have to do with the fact that myIns1.ExecuteNonQuery() throws an error even though the insert is successful.
-EDIT- I discovered that the "duplicate values" error is because it is somehow attempting to insert the record twice. I have no idea why it's doing that though.
The following line of code gives a warning with Resharper: 'Comparison of floating point numbers with equality operator. Possible loss of precision while rounding values.'
Dim samples() As Single If samples(i) = Nothing Then samples(i) = _mPreviousSamples(i) End If
What is the best way of checking if a value is present?
I am trying to figure out how to check a string can contain a certain value.In the begining I had a checkbox and wanted to hide a ceratin field depending upon which checkboxes were selected.The problem with this is that the value is always = to the first value.
I got around this by writing these values into a hidden textBox and using a loop.So now I have a textbox and if the user selected the 1st and 3rd choice the textBox would = "AC" If they selected all choices it would = ABCD etc...How can I determine if the values in my textBox contains just letter 'B' ?
I tried this:
-------------------------- Dim values As String = [String].Empty For Each item As ListItem In section2List.Items If item.Selected Then
I've been wondering how to do that for a while. (I never really needed it so far ). I wanna make e.g. a simple alarm script (waits for 6.30 am and makes a beep). The only way I could think of it is make a loop in the main function which loops until 8 hours later. Is there any other, more civilized way (probably event?)
How do I check which functions are in a dll I don't who's contents are unknown to me? I am looking to use a certain function and I have a couple of dlls and I don't know in which one it is are its name. So i need to be able to show all function available in a dll and their parameters.
