IErrorInfo.GetDescription failed with E_FAIL(0x80004005).I get this error when trying to send a query to a database. Its an access 2000 DB. Google suggests the error indicates that I am using a vb keyword as a field name or table name. I have checked with these here and can't see anything that matches.
View 6 RepliesI have some sql statement error while querying the DB and to display the result on a data grid view. Could someone check the codes below and let me know the problem with the codes.
Dim cm As New System.Data.OleDb.OleDbCommand
Dim rd As System.Data.OleDb.OleDbDataReader
Dim Conn As OleDbConnection
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I have the following NHibernate Linq query:
From eachLine In myNhSession(Of SamplePoco)()
Where eachLine.SampleIntField = 1234
The property SamplePoco.SampleIntField is type Nullable(Of Int32)
When I run the query, I get the following exception:
System.InvalidCastException: Unable to cast object of type 'NHibernate.Hql.Ast.HqlCoalesce' to type 'NHibernate.Hql.Ast.HqlBooleanExpression'
If I change the property type to Int32, it works. It seems that Nullable types are automatically converted into a coalesce expression by the Linq compiler.
Debugging the NHibernate, I just found out that this Where clause was converted into: {where ((eachLine.SampleIntField == 1234) ?? False)}. As I can understand, the whole condition comparison was translated to be coalesced instead of just the Nullable property.
If I put this way eachLine.SampleIntField.Equals(1234) it doesn't work as well ('Equals not implemented' exception)
If I change the query to the following code, it works:
From eachLine In myNhSession(Of SamplePoco)()
Where {1234}.Contains(eachLine.SampleIntField)
Another code that works as well (coalescing the field properly as I was expecting by the first query):
From eachLine In myNhSession(Of SamplePoco)()
Where If(eachLine.SampleIntField,0) = 1234
I'm using VB.net for a project i'm building for a friend. He has access to data on all the schools in our country and also data on the local area Authorities which run these schools. I have a database with two related tables; 'TBLlocalauthority' and 'TBLschools'. Each localauthority can have several schools, but each school can only have one local authority.
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Is there a particular class in .NET available that will allow a user to query IIS to see what websites are running on the local server? I would like to try to write a simple program that programmitically lets me know which websites are running in IIS along with some basic information about them. Can this be done in VB?
View 3 RepliesWhenever I have
Dim catID as integer
And I use this in a query like this:
cmd.CommandText = "select * from categories where parentid='" + catID + "'"
I get:
Conversion from string select * from categories where p to type Double is not valid.
Why is it so?The parentid datatype in sql is integer.
My form has a DateTimePicker and a DataGridView on it. I need to have it query a SQL Server DB and return the table to the DGV. The query is to search the Date_Joined field for date less than the date that the user input with the DTP. With the code below, my DGV is populated with all data and not the filtered data I need. I also have added a Go button for the purpose of execution instead of using the ValueChanged sub for the DTP.
Private Sub btnGo_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnGo.Click
Dim query As String
'dtpDateJoined is a DateTimePicker on the form
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Is it possible to re-use a DataTable in .net? Here's an example from code-behind:
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I`d like to do a query to a SQL server database using the statements like "SELECT...FROM...." an so on. Then I`d like to save results of the query to an array or other variables. I`d like to handle the data of the query results "manually". I don`t want to use the datagridview and tableadapters and so on which are created when I drag a table from the datasources window to the form. is the ADO.NET and datasets the right tool at all? If yes, I believe these are the first steps needed:
- create a connection string
- create a connection and open it
- create a dataadabter
- create a dataset and populate it with the dataadabter
The first problem is the connection string. When I create a connection to a new data source in datasources window, a string is created and saved to some configuration file. Can I use it and how?
Basically for normal select queries from my database I have no problems as I would put the following and then bind it to a controller to display the iteam, however now I am trying to query sum of a field from the database, but I think it should be different as It's giving a Nullable value:
SELECT SUM(PointsRedeemed) AS tAward
FROM [Transaction]
WHERE (BusinessId = ?) AND (CardNo = ?)
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the remaining code for my vb.net project? In my Project, I have a table name tblBatch that has a field name btchGravel. Since in my project, a field name gravel has more than 10 inputs from the 10 textboxes in my main form. I manage to save it in this manner:
'Save the textboxes in a single string, separated by comma
Dim GravelLine As String
GravelLine = txt1G.Text & "," & txt2G.Text & "," & txt3G.Text _
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I am trying to create a stock scanner which allows users to filter stocks based on multiple criteria that they select. Like the following example with 2 criteria:
Criteria 1 Filtered Result: StockA, StockB, StockC, StockD
Criteria 2 Filtered Result: Stock B, Stock C, StockE, StockF
SCANNER RESULT: Stock B, StockC (ideally this result would be displayed in a GridView)
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Given the following XML file:
<users>
<user name="admin" password="foobar" roles="Admin,Guest" />
<user name="guest" password="foobar" roles="Guest" />
</users>
How do I find a specific node? In this case I want to find the node that has its name attribute to be "admin"
Dim authGroup As XElement = XElement.Parse(myXMLDoc.OuterXml)
Dim foundUser As IEnumerable(Of XElement) = From i In authGroup.Elements Where i.Attributes("name") = "admin" Select i
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good afternoon people, i got a problem here on my program, i need to query from a different tables in database but it gives me error, here is my code
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vb
Dim conn As New OleDb.OleDbConnection(ConnStr)
conn.Open()
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I have a DataTable filled with employee names and hours. I want to query that data to make a list of all the unique employees and the total hours for each, but I don't know how to do that. If I were to query the database directly I would do something like this
View 6 RepliesI have been looking into dynamic querying of datasets and the use of copytodatatable() for a project. I have seen in alot of forums that the copytodatatable functionality is unusable as it was removed. have an example of a dynamic Linq query being loaded into a datatable.
View 1 RepliesI'm using this function to return a value from multiple databases across three SQL instances (On the same server). I'm looping though a DataGridView that lists all the databases on one of the three SQL instances.Is there a faster way of doing this? It's quite slow using this method.
Function DatabaseStatus(ByVal SQLServer As String, ByVal Database As String)
Dim myConn As New SqlConnection("Server=" & SQLServer & ";User Id=USER;Password=PASSWORD;Database=" & Database & ";")
Dim Status As String = ""
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How do I return a top 5 with rank number using linq?
Dim Top5 = From A In DAO.Cache.Select(Of VO.Empresa).Take(5) Select A.Nome
I would like this result:
Rank Name
1 "Example Name"
2 "Example Name"
3 "Example Name"
4 "Example Name"
5 "Example Name"
querying a remote Access database! We are currently using this because thus far we have failed at hooking up a sp_linkedserver. I feel like it's a terrible hack and want to be done with this whole network mapping business once and for all!
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I am querying a date from my Access 2007 database in the format: MM/DD/YYYY It's then saved as a string
Depending on the month and day, it might be 1 or 2 characters. To set the DateTimePicker, it takes it as this format: DateTimePicker.Value = New DateTime(YYYY, MM, DD)
How can I switch around the characters in my string so that it can satisfy the format the DateTimePicker wants? I was thinking about some kind of reader that "consumes" characters until it reaches a delimiter ("/") and then does something with it. I remember doing that in JAVA but not in VB.NET
I am having a problem saving related tables and querying them. I have both data binding sources on the form and I have both being added, end edit, and both being saved. When I "view all" and click on the related table "crimes" they're not showing with the Inmate that committed them. I have gotten it to do this with a code similar to that below and I am wondering what I'm doing wrong so that the datagridview for crimes will display the correct crimes for the correct inmate. The primary key for inmates is DOC# and the Primary Key for Crimes is "Entry ID"
Private Sub btnSave_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnSave.Click
Me.Validate()
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I'm trying to open a connection and create an SQL statement with two different tables in different Access DBs. Is this possible? I'd like to join the tables in a query.
Is there a great advantage in splitting somewhat large Access databases? Or is it best to just create a large access database with many tables?
i would like to check the possibilities to draw out data from a data grid, which is currently showing out some data in it.the datagrid contains 2 columns in it,but will display only one column at run time. The result is assumed to get changed according to some parameter values.
So i need to query the value of first column and i need to use it as parameter for a report in report viewer.i am trying it in VB.NET.Kindly let me know whether the above is possible? if so please do let me know how to start.
I am trying to query from search box using list of data and the linq I used is:data = (From k As BSPLib.ContactLib.Contact In data_org.Values Where k.stringdata Like "%" & Searchtxtbox.Text & "%" Select k.prime).ToListBut this is not working, I am getting no data at all. Data_org is a dictionary so I used the values; k.stringdata contains all the data that need to be searched. Searchtxtbox.text contains the user defined search item.I Tried with sqlmethods through linq, but sqlmethods does not exist for me, I tried with with Imported namespace yet the code is not showing sql methods, could you please provide a workable query or just tell me where I have gone wron
View 2 RepliesNot sure if I am using the correct term, but it's not child/parent since they aren't nested objects. In my application I've got a User, UserUserGroup, and UserGroup objects which are pretty standard, UserUserGroup is a linking object with corresponding IDs. I am using Linq-to-SQL so unforunately it doesn't used nested objects, but it still knows the relation.
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I have multiple web applications that I've built for our intranet. I wanted to allow users to not worry about logging in, so these apps pull the currently logged on user when they hit the site. I used this code for this to happen:
Dim userName As String = User.Identity.Name
CurrentUser = userName.Substring(userName.IndexOf("") + 1)
This works like a charm, no issues here. The next step is to query Active Directory for that logged in user to pull various information. How I currently have it coded, it works like a charm on the devleopment side (typical because I'm not running IIS).The problem becomes when I publish it to my IIS server (Windows Server 2008 R2 running IIS 7.5), I get error messages that point to the specific line in my code that queries Active Directory. The interesting part is these apps were working great last week. They broke after my server admin did the latest batch of Windows Updates (please note, I am running them using .Net Framework 4.0)Before I had each app setup so that Windows Authentication was Enabled, the other Authentication types were disabled. For providers, Negotiate is #1, NTLM is #2. For Advanced Settings, Extended Protection = Off, and Enable Kernel-mode authentication is checked.
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In doing this I also removed the string that was higher up in my web.config section. This did not work either (fyi, this was a great reference[url]I then tripped across this article: [url] which seemed to be a similar situation. This article eventually referenced "Double Hops", after looking into this and trying a few things, this didn't solve my issue either.Next StepI am going to try a new IIS 7.5 implementation on a different Server 2008 R2 system and essentially start from scratch, to see if the problem recreates or not.
I am trying to get my code working as per the instruction on [URL]So far I have the wrapper:
Public Delegate Function PredicateWrapperDelegate(Of T, A)(ByVal item As T, ByVal argument As A) As Boolean
Public Class PredicateWrapper(Of T, A)
Private _argument As A
Private _wrapperDelegate As PredicateWrapperDelegate(Of T, A)
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Then I try to call it from my code:
Dim children As List(Of String) = toplevel.FindAll(New PredicateWrapper(Of Integer, Integer)(Did, AddressOf DidMatch))
I then get an error on DidMatch ... Error Method 'Public Function DidMatch(item As DeptMenuData, did As Integer) As Boolean' does not have a signature compatible with delegate 'Delegate Function PredicateWrapperDelegate(Of Integer, Integer)(item As Integer, argument As Integer) As Boolean'.
I am trying to autocomplete a Textbox using the AutoComplete Extender. My Web Service is as Follows:
Code:
Imports System.Web
Imports System.Web.Services
Imports System.Web.Services.Protocols
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I'm looking for the most efficient way to query an Access table from VB.Net. I think throughout the life of a run I'm going to need to query the table ~1,000,000 times. I'm using Access 2003 to hold my data. What I've been doing so far is this:
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