When I use the dataAdapter.fill(ds,tableName), it reports an error: "Failed to enable constraints."Yes, I changed the selectcommand.I know if I modified the selectcommand, and if it will take diffrent columns result, this error will be reported.
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There were three similar questions in StackOverFlow but none gave an answer.. If have found why this error in occurring but don't know the fix. I am using Strongly Typed Dataset for my project which is created as a dll for DAL. I have added the Sql Server Table into this dataset using the designer and has created a DataAdapter
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I keep getting this error message (see image). What's weird is it's coming from a "typed" dataset that is bound to a DataGridView and even though I get this message, the DGV still loads with all the data. I've bound this dataset to the DGV thru the designer. Here is the line of code that is erroring out:
Me.adpItemMaster.Fill(Me.JewelryDBDataSet18.tblItemMaster)
I checked the table and the primaryKey for the tblItemMaster is unique for each row.
I am getting headache analyzing what's causing this error message "Failed to enable constraints. One or more rows contain values violating non-null, unique, or foreign-key constraints."I have 7 different sections, each sections has the same subject component, one of which is CLUB. The error will only display for one particular section but for the rest of the sections, the program work fine. All sections uses the same code that's why I am very puzzled with the error. if the code works for the rest of the section one it fails for the one particular section?I have check my table (sql2005 express) and all the records are intact.The error is pointing on da.Fill(Me.Grading_Rpt_DataSet.tblEnrol)of the code below.
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I am using/creating a DataTable so the "enforceConstrains" property is not avilable for DataTable.Error message: Failed to enable constraints. One or more rows contain values violating non-null, unique, or foreign-key constraints.
Windows Form Load Event:
Private Sub Expenses_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
expensesGV.DataSource = listExpenses()
expensesGV.Columns(0).Visible = False
End Sub
I am trying to add a parameter to a sqlDataAdapter. I have tried to use parameters.add() but the adapter is not a sqlCommand. Here is some of my code.
Private Sub convertToCSV(ByVal SqlQuery As String)
Dim Dt As New DataTable()
Dim SqlCon As New SqlConnection("Data Source=db;Initial Catalog=productionservicereminder;User Id=id;Password=pass;")
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Basically I am trying to do something like this:
Ada.Parameters.Add(New SqlParameter("@pgid", pgid))
There is no other workaround at this point, so here is what I am attempting to do:
1. Fill a DataAdapter from an Excel.xls spreadsheet.
2. TRUNCATE an existing SQLServer2005 db table that matches this excel spreadsheet.
3. UPDATE that SQL Table with the DataTable filled from the excel spreadsheet.
If there are anyother suggestions (OPENROWSET/DATASET is not possible for my situation, in or outside of a SProc),Here's the current dev point I am at --- no errors, but also the SQL table does not update.
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I have a problem with access database in my vb project. I would like to fill the listbox with objects from my database. I've attached two images. In first image when i'm using command objDataAdapter.Fill(mydataset....) i can select table property(zaposlen). But in second image or in my second app i dont have an option to select table property in my dataset(there is nothing to select). If i select DataTableDataTable i get next error: DataTableDataTable' is a type in 'WindowsApplication1.baza_podatkovDataSet' and cannot be used as an expression.
View 2 Repliesi try to use this yesterday it work fine..now, it will process too slow.. when fill the dataadapter into the dataset..here is the code it gives 20 menutes still no result.. "no error, no comment. it's like standby
Dim conn1 As MySqlConnection = New MySqlConnection("server=pc1;user id=user;Password=12345;persist security info=True;database=mytsmobile")
conn1.Open()
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[code]Where I add my parameter, I am trying to have it pull records that contain the text that is in the jpDescTextBox instead of being exactly equal to it. I have tried using wildcards such as * and %.
View 7 RepliesI there a way to set up my DataTable so a field (or all fields can allow nulls if you can't set just 1 field) so oIDbDataAdapter.Fill won't leave out DataRows where a field contains a null value?
Dim oSqlCommand As SqlClient.SqlCommand
Dim oIDbDataAdapter As System.Data.IDbDataAdapter
oSqlCommand = New System.Data.SqlClient.SqlCommand( _
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VB2010, MySql I have a dataview generated from a datatable using a rowfilter.I have event handlers listening to the dataview.listchanged event. To keep the datatable (in memory) in sync with the mysql database (on a remote server), i issue datadapter.fill commands every now and then, the objective being that only the changed rows in the datatable (as a result of the fill) would generate a listchanged event on the dataview.To my surprise the dataview_listchanged event fires after refresh by the dataadapter.fill method, however the ListChangedType it gives is: ListChangedType = reset. I would have expected a ListChangedType.ItemChanged for every changed datarow.Since the dataview is used to populate a large storage yard, i am now forced to repopulate the whole storage yard, which is a time consuming business.Is there a way to only generate DataView.ListChanged events for rows in the datatable that are actually changed by the datadapter.fill method?
View 2 RepliesAt the top of my code for the form I have the following statements (and some other unrelated ones to):
Dim LastDataRow As DataRow
Public Event RowChanged As DataRowChangeEventHandler
When my form loads I run the following line of code:
AddHandler dt.RowChanged, New DataRowChangeEventHandler(AddressOf Row_Changed)
After the form loads I have a FetchData button which connects to the database and brings the records into a datatable object. During this fill operation my Row_Changed event fires (for every record I think) and tries to run DataAdapter.Update(DataTable) (pseudocode) which ultimately fails because I haven't yet created commands. The error I get in my Row_Changed procedure is:
Update requires a valid InsertCommand when passed DataRow collection with new rows.I hadn't even planned to use an InsertCommand at all since I will not be allowing users to insert records from this form. I do plan to allow them to delete or modify existing records, but not insert new ones.run my AddHandler statement after filling the datatable. However, I'm trying to figure out how to rewrite my code so that I can refresh the datatable without closing out the form/application and having to open it up again. I think that's a problem for a separate discussion.
After running the following sub (VS debugger), I try to detach the database in SSMS, but it shows the connection open still and won't let me detach. If I close program in debugger, the database shows no connections. I check the dataadapter's connection in the finally block and is shows closed. What gives
Private Function ClientMasterDBFiles(ByVal MasterClientDBConnection As String, ByVal DBName As String) As DataTable
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I want to allow the user to enable or disable a textbox by clicking either a button (enable) or the reverse. (disable) if the user clicks the enable button the textbox should receive the focus.
View 4 RepliesI have the a function that is declared like so: Public Sub Modify(Of SIMType As {New, DAOBase})(ByVal obj As SIMType)
I also have a class called Products which is declared like so:
Public Class Products Inherits DAOBase
So as you can see, if I were to call this function like so:
Modify(Of Products)(new Products())
This would not be an issue. The issue actually arises when I try to cast the object being past in to its real type. For example: both do not work. I get a Value of type SIMTYPE cannot be converted to IMS.Products error. Im assuming this is because I am using generics. Is there a way to adjust my function to allow for a casting operation like I am trying to do? In the end, what I need is a reference of the actual type (Products in this case) to the object.
Can some one explain what constraints are in this application?
View 11 RepliesConsider the following extension method:
<Extension()> _
Public Function Satisfies(Of T)(ByVal subject As T, ByVal specification As ISpecification(Of T)) As Boolean
Return specification.IsSatisfiedBy(subject)
End Function
This works as expected if subject is the exact class being operated on by the specification. However, if the specification is examining the super-class of T, this extension will not work unless subject is explicitly cast to the super-class. Is there a way I can avoid this? So far, the best I've been able to come up with is:
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Since I (apparently) can't get this to work exactly as I'd like in VB.NET due to limitations in the language itself, is my second attempt the safest/most efficient way to do this?
I am starting to play with extension methods and i came across with this problem:In the next scenario i get a: "extension method has a type constraint that can never be satisfied"
Public Interface IKeyedObject(Of TKey As IEquatable(Of TKey))
ReadOnly Property InstanceKey() As TKey
End Interface
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I'm trying to use a DataTable to get the schema of a SQL Server DB.But, when try to detect the ForeignKeys, the constraints collection only brings the UNIQUE constraints.
Private Sub ShowConstraints(ByVal tableName As String)
Dim table As DataTable = New DataTable(tableName)
Using connection As SqlConnection = New SqlConnection(GetConnectionString)
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How can I get the ForeignKey Constraints?
How do I add constraints to image resizing code? I want the image to be no larger then 165x146. The below code does not hold the constraint when image is 525x610.[code]
View 1 RepliesI am doing a projectin VB 2008..I ave list of data being displayed in listview and it gets stored in DB..The problem is,i am unable to filter particular data based on some constraints like date,client etc.. How can i filter data based on various constraints..As i am new to VB,
View 5 RepliesI have a generic function in VB.Net. I also have two classes called A and B. Is it possible to allow the generic constraints on my function to allow the Type to be either class A or B? Class A and B do not share any base classes except for object.
View 1 RepliesI'm using Visual Basic Express 2010 and SQL Express 2008 in Windows XP. At first I couldn't add a datasource (the .mdf file for the database) because of a "Operating system error 32" which I seemed to have resolved by giving myself full permissions for .mdf file (by right clicking on the file and going into properties and then Security) and restarting the SQL SERVER (SQLEXPRESS) service. The dataset for the database is in my solution explorer but when I right click on a table adapter to add a query and attempt to open up the query builder, I get the error in the title above.
View 1 RepliesI'm working on my first real asp.net web application and I'm kind of stumped on the best place and method to trap and handle database constraint violations. Suppose I have a unique constraint on a column and a user inputs something that would violate that unique constraint. Do I catch it in the business layer by making a call to the database to check of the value exists for that column or do I let it go all the way to the database and let it throw an exception and handle that in my application?
I don't like the latter answer- because it makes sense to handle as much as you can in the business layer before it reaches the database. But it's also somewhat problematic as my application is driven by procedures that implement basic CRUD operations on all tables. So in order for me to enforce uniqueness in the business layer, I need to create a procedure for every possible constraint so I can do a look up before an update or insert. That just seems tedious... and I'm duplicating business rules as they exist in both the database and the business layer, so if something changes, not only do I have to change the database, but I have to change the procedure and the application code.
So is there a right way or a good way to enforce these database constraints in application code or should I be looking at a way to catch exceptions thrown by the database and present them in a user-friendly way?
I'm trying to write a class that will be in charge of persisting application options. Since the options need to be persisted the values that I'm sent must be serialisable.
Initially I thought I've be able to write a method with a signature like this[code]...
I'm using Visual Basic Express 2010 and SQL Express 2008 in Windows XP.I created a database on my local PC HDD. At first I couldn't add a datasource (the .mdf file for the database) because of a "Operating system error 32" which I seemed to have resolved by giving myself full permissions for .mdf file (by right clicking on the file and going into properties and then Security) and restarting the SQL SERVER (SQLEXPRESS) service.The dataset for the database is in my solution explorer but when I right click on a table adapter to add a query and attempt to open up the query builder, I get the error in the title above.
View 10 RepliesWhen I write the following statement in VB.Net (C# is my normal language), I get an "end of statement expected" referring to the "Implements" statement.
<Serializable()> _
<XmlSchemaProvider("EtgSchema")> _
Public Class SerializeableEntity(Of T As {Class, ISerializable, New}) _
Implements IXmlSerializable, ISerializable
...
End Class
The C# version that I'm trying to emulate is:
[Serializable]
[XmlSchemaProvider("MySchema")]
public class SerializableEntity<T> : IXmlSerializable, ISerializable where T : class, new()
{
....
}
I created a typed dataset a day or so ago, then I added a whole bunch of tableadapter/tables with some relationships etc... suddenly out of nowhere it decides my dataset "is not defined". everywhere in my code where i use this dataset now has an error. I tried not to pull out my hair and do a Clean then Rebuild solution... out of nowhere it just refuses to generate code. Object reference not set to an instance of an Object. It would be nice if it was my object so i could find it but it's not.
Curiously I also lost the little database icon on the dataset in the solution explorer.I can still open it in the designer and preview my queries etc... it just wont make the code. it's driving me insane. anyone got a solution?
I have datagridview1 binded to data Table1 (with binding source) . This data table1 is in relation with his child data table2.When I insert new record to table1 I want to refresh datagridview1.
If I use table adapter fill method I get error.TableAdapter1.Fill(Me.DataSet1.Table1) ' error error: Cannot clear table Table1 because ForeignKeyConstraint FK_Table1Table2 enforces constraints and there are child rows in Table2.