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If the database design is wrong, you don't "live with it"; you change it. Most "DBA's" have no practical application experience and design "from a book"; where performance and ease of use takes a back seat to 4th normal form.
"Before entering on an understanding, I have meditated for a long time, and have foreseen what might happen. It is not genius which reveals to me suddenly, secretly, what I have to say or to do in a circumstance unexpected by other people; it is reflection, it is meditation." - Napoleon I
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I completely agree with you Gerry.
The reality is we did make some changes to the DB but is sticky about this is that users are insistent on having the ability to search for and retrieve existing data and the change I need to make will make that nearly imposssible.
So, yea, I have to live with this.
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Change can be introduced in different ways. You can extend; once the extension works; you cut away the part(s) the extension replaces. If you need to "stop" the system to make a change, it's the wrong kind of change. They didn't remove the Frank Slide; they built a new road around it.
"Before entering on an understanding, I have meditated for a long time, and have foreseen what might happen. It is not genius which reveals to me suddenly, secretly, what I have to say or to do in a circumstance unexpected by other people; it is reflection, it is meditation." - Napoleon I
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Ihechi Alozie wrote: I have delayed giving management demo and they have insisted that I show something by wednesday March 15th.
Show them this message.
Ihechi Alozie wrote: I am asked to not discard the current DB design to "work with what I have."
And how, does management know that such is better than adapting the damn thing? What programming knowledge do they bring to the table to say whether or not that is a good idea or even viable?
Would you hire a damned plumber and tell him not to use pipes? Do you tell the surgeon how to do his job? You hired a programmer for his knowledge. If yours is superior, you don't need him.
The damned db IS the problem! If you keep that, you insist on keeping the core problem. Tell the programmer to normalize the DB design first. Then migrate the DB overnight and move on.
If your toilet-selling company is listed on the stock exchange, then I will be betting on you loosing money. If I need to judge you as a company, just imagine the sound of a toilet flushing.
Let the dev do the dev thing, and you keep managing the stuff that needs managing. I'm not joking; you handicapped a dev, and set him up for failure. Now, he needs to "show a demo" of something that doesn't work because you arbitrarily decided so.
Normalize the DB. Adapt your app to work with it. Then migrate all data. Work from there or accept that the company will be "bits".
I would help your dev to do so; on the one condition that you stop interfering with his work. Trust in the employee.
Bastard Programmer from Hell 
"If you just follow the bacon Eddy, wherever it leads you, then you won't have to think about politics." -- Some Bell.
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You guys are on point.
Thank you guys for your useful inputs.
I will keep tearing away at this, slowly but surely.
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Slow but sure wins any race.
Bastard Programmer from Hell
"If you just follow the bacon Eddy, wherever it leads you, then you won't have to think about politics." -- Some Bell.
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I have been looking at the code that gets generated when you add new scaffold items for Identity into an web application. I notice that often a UserManager<TUser> gets injected along with a SignInManager<TUser>. It seems that the SignInManager has a property for UserManager. Is there a reason to have them injected separately instead of just injecting and using the SignInManager? Can there be situations where the UserManager property is null in the SignInManager but would have been injected into the constructor?
var userId = await _userManager.GetUserIdAsync(user);
var userId = await _signInManager.UserManager.GetUserIdAsync(user);
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It comes down to separation of concerns.
SignInManager is used by the UI to get credentials, authenticate, and maintain login state, while UserManager is concerned with managing the database of users and authenticating credentials passed to it by a SignInManager.
Yes, the SignInManager has a UserManager property, but you have to pass a configured UserManager to the SignInManager when creating an instance of that.
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Yes, ASP.NET Identity requires distinct SignInManager<TUser> and UserManager<TUser> classes.
The management of user accounts, including their creation, updating, and deletion, password resets, and email address confirmations, is under the purview of the UserManager<TUser> class
SignInManager<TUser> class is responsible for handling the authentication and sign-in process for the application
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This is my first time that i post here and i hope that topic is correct is placed.
Please who can help me?
Error message is:
An unhandled exception of type 'System.InvalidCastException' occurred in System.Data.dll
Additional information:
This rows give error (the code was writed for MySQL and i have self changed to MS Access):
Dim len As Long = rd.GetBytes(0, 0, Nothing, 0, 0)
Dim array(CInt(len)) As Byte
rd.GetBytes(0, 0, array, 0, CInt(len))
pic = New PictureBox
Dim ms As New System.IO.MemoryStream(array)
Dim bitmap As New System.Drawing.Bitmap(ms)
pic.BackgroundImage = bitmap
Full Code:
Imports System.Data.OleDb
Public Class Form1
Dim con As OleDbConnection
Dim cmd As OleDbCommand
Dim rd As OleDbDataReader
Private WithEvents pic As New PictureBox
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
End Sub
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
'Dim con As OleDbConnection
'Dim cmd As OleDbCommand
'Dim rd As OleDbDataReader
con = New OleDbConnection("Provider=Microsoft.ACE.OLEDB.12.0;Data Source=|DataDirectory|\database.accdb;")
con.Open()
cmd = New OleDbCommand("select * from MyTable", con)
rd = cmd.ExecuteReader
MsgBox("connected")
con.Close()
MsgBox("disconnected")
End Sub
Sub LoadData()
con = New OleDbConnection("Provider=Microsoft.ACE.OLEDB.12.0;Data Source=|DataDirectory|\database.accdb;")
con.Open()
cmd = New OleDbCommand("select * from MyTable", con)
rd = cmd.ExecuteReader
While rd.Read
Dim len As Long = rd.GetBytes(0, 0, Nothing, 0, 0)
Dim array(CInt(len)) As Byte
rd.GetBytes(0, 0, array, 0, CInt(len))
pic = New PictureBox
Dim ms As New System.IO.MemoryStream(array)
Dim bitmap As New System.Drawing.Bitmap(ms)
pic.BackgroundImage = bitmap
FlowLayoutPanel1.Controls.Add(pic)
End While
rd.Close()
con.Close()
End Sub
Private Sub Button2_Click(sender As Object, e As EventArgs) Handles Button2.Click
LoadData()
End Sub
End Class
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sdfsdfsdfewrew3feff wrote: This is my first time that i post here
And yet you've apparently been a member for 12½ years, and posted 22 messages. Did you mean this is your first post in the ".NET Core" forum? Or have you managed to grab someone else's account by mistake?
sdfsdfsdfewrew3feff wrote: select * from MyTable
If you're only reading one column, then only select that one column. If you use select * from ... then you're subject to the whims of the database engine as to which order the columns are returned in.
You're presumably getting the InvalidCastException on the rd.GetBytes line, which suggests the first column being returned by your query is not your image column.
"These people looked deep within my soul and assigned me a number based on the order in which I joined."
- Homer
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Sorry, Richard. I was forget and it long time ago.
When i select a column than i get new error "From".
Additional information: The FROM clause contains a syntax error.
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The only queries you've shown are select * from MyTable, which wouldn't produce that error.
Perhaps your real table name is a reserved word?
"These people looked deep within my soul and assigned me a number based on the order in which I joined."
- Homer
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sdfsdfsdfewrew3feff wrote: This is my first time that i post here
No it's not! I remember you from a couple of exchanges about 8 years ago.
You're FINALLY providing proper detail to actually help you this time! 
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Hi Dave Kreskowiak, i was forget and you me not.
Long time ago i have download opensource projects.
Welcome back Dave and how are you?
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sdfsdfsdfewrew3feff wrote: "select * from MyTable"
Using the asterisk means the database is free to return the columns (all columns) in any order that it wants.
So if your table as more than one column then you have no idea at all what the first column actually is.
Thus if you assume that the first column is of a certain type like a varchar but you use it like an int, and code it that way, then you will get errors. Very like a cast error.
Your SQL should look like the following.
select col1, col2, col3 from MyTable
If you only want one column then of course only specify those.
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----The Sample XML File
<AuditResult name="Server Baseline" created="2/14/2023 3:16:19 AM" type="Assessment run by Administrator">
<Section name="Operating System" state="Compliant" further-state="">
<Result name="Computer Name" type="report">DEVSTUDIO </Result>
<Result name="Operating System" type="report">Microsoft Windows Server 2008 R2 Standard </Result>
</Section>
<Section name="Operating System (Windows Server 2008 R2)" state="Not Compliant" further-state="">
<Result name="System Partition" type="compliance" state="Compliant" further-state=""> </Result>
<Result name="Role & Feature - .NET Framework" type="compliance" state="Compliant" further-state=""> </Result>
<Result name="Windows Firewall - Private Profile Off" type="compliance" state="Compliant" further-state=""> </Result>
<Result name="Windows Firewall - Domain Profile Off" type="compliance" state="Compliant" further-state=""> </Result>
</Section><code></code>
</AuditResult>
------------------
The above is my xml file, i am using dataset to populate in the gridview i am able to get the child node information but along with parent i am unable to do it. PFB the code
Dim Opf As New OpenFileDialog()
Opf.Filter = "XML File | *.xml"
Opf.FileName = ""
If Opf.ShowDialog() = DialogResult.OK Then
Dim fcontent As String
Dim fpath As String
fpath = Opf.FileName
Using sr As StreamReader = New StreamReader(fpath)
DataGridView1.AutoSizeColumnsMode = DataGridViewAutoSizeColumnsMode.AllCells
DataGridView1.AutoSizeRowsMode = DataGridViewAutoSizeRowsMode.AllCells
DataGridView1.DefaultCellStyle.WrapMode = DataGridViewTriState.True
fcontent = sr.ReadToEnd
'MsgBox(fcontent)
Dim sfcontent As StringReader
sfcontent = New StringReader(fcontent)
Dim doc As XmlDocument = New XmlDocument()
doc.Load(sfcontent)
Dim naudit As XmlNode = doc.SelectSingleNode("/AuditResult/@name")
Dim naudita = naudit.InnerText
nlblaudit.Text = naudita
Dim nauditc As XmlNode = doc.SelectSingleNode("/AuditResult/@created")
Dim naudit1 = nauditc.InnerText
Dim nauditb As XmlNode = doc.SelectSingleNode("/AuditResult/@type")
Dim naudit2 = nauditb.InnerText
nlblauditcreated.Text = naudit2 & " - Created" & " : " & naudit1
Dim ds As New DataSet()
ds.ReadXml(New StringReader(fcontent))
DataGridView1.DataSource = ds.Tables(2)
For i As Integer = 0 To Me.DataGridView1.Rows.Count - 1
If Not IsDBNull(Me.DataGridView1.Rows(i).Cells(2).Value) Then
If Me.DataGridView1.Rows(i).Cells(2).Value = "Compliant" Then
Me.DataGridView1.Rows(i).DefaultCellStyle.BackColor = Color.LightGreen
ElseIf Me.DataGridView1.Rows(i).Cells(2).Value = "Not Compliant" Then
Me.DataGridView1.Rows(i).DefaultCellStyle.BackColor = Color.LightPink
End If
End If
Next
End Using
End If
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I have recently starting getting a memory resources error with System.Design. The application has been running fine for years and this just started popping up without any code changes. This has been encountered on multiple PCs.
Could not load file or assembly 'System.Design, Version=1.0.5000.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a' or one of its dependencies. Not enough memory resources are available to process this command. (Exception from HRESULT: 0x80070008)
The application is running on .NET 4.6.1. The app is taking up around 400 MB of memory and I have over 10 GB RAM free on my PC. So I don't think it is a PC resource issue.
After the error occurs I start seeing issues in the OpenFileDialog. The icons are black squares and parts of the UI of the form don't show up. The file name and file type drop down will be missing.
Here is the stack trace:
at System.ModuleHandle.ResolveType(RuntimeModule module, Int32 typeToken, IntPtr* typeInstArgs, Int32 typeInstCount, IntPtr* methodInstArgs, Int32 methodInstCount, ObjectHandleOnStack type)
at System.ModuleHandle.ResolveTypeHandleInternal(RuntimeModule module, Int32 typeToken, RuntimeTypeHandle[] typeInstantiationContext, RuntimeTypeHandle[] methodInstantiationContext)
at System.RuntimeType.RuntimeTypeCache.MemberInfoCache`1.PopulateNestedClasses(Filter filter)
at System.RuntimeType.RuntimeTypeCache.MemberInfoCache`1.GetListByName(Char* pName, Int32 cNameLen, Byte* pUtf8Name, Int32 cUtf8Name, MemberListType listType, CacheType cacheType)
at System.RuntimeType.RuntimeTypeCache.MemberInfoCache`1.Populate(String name, MemberListType listType, CacheType cacheType)
at System.RuntimeType.RuntimeTypeCache.MemberInfoCache`1.GetMemberList(MemberListType listType, String name, CacheType cacheType)
at System.RuntimeType.GetNestedTypeCandidates(String fullname, BindingFlags bindingAttr, Boolean allowPrefixLookup)
at System.RuntimeType.GetMember(String name, MemberTypes type, BindingFlags bindingAttr)
at System.Type.GetMember(String name, BindingFlags bindingAttr)
at Microsoft.VisualBasic.CompilerServices.Symbols.Container.LookupNamedMembers(String MemberName)
at Microsoft.VisualBasic.CompilerServices.Symbols.Container.GetMembers(String& MemberName, Boolean ReportErrors)
at Microsoft.VisualBasic.CompilerServices.NewLateBinding.LateSet(Object Instance, Type Type, String MemberName, Object[] Arguments, String[] ArgumentNames, Type[] TypeArguments, Boolean OptimisticSet, Boolean RValueBase, CallType CallType)
at Microsoft.VisualBasic.CompilerServices.NewLateBinding.LateSet(Object Instance, Type Type, String MemberName, Object[] Arguments, String[] ArgumentNames, Type[] TypeArguments)
at FormLookAndFeel.ApplyTheme(Object& source, List`1& lstIgnoreTheme, ToolStripType& toolStripType) in C:\Users\JoshWilliams_k0t30jx\Documents\PROJECTS\Sherpa\COM_v1\Theming\FormLookAndFeel.vb:line 47
at FormLookAndFeel.BlueTheming(Object& form, List`1& lstButton, List`1& lstHeading, List`1& lstIgnoreTheme, ToolStripType& toolStripType) in C:\Users\JoshWilliams_k0t30jx\Documents\PROJECTS\Sherpa\COM_v1\Theming\FormLookAndFeel.vb:line 17
at frmAdmin.frmAdmin_Load(Object sender, EventArgs e) in C:\Users\JoshWilliams_k0t30jx\Documents\PROJECTS\Sherpa\COM_v1\frmAdmin.vb:line 1225
The code that encounters the error loops through all controls on the form and sets the font size, fore color and back color based on control type. As I said above this has worked for years without an issues. This just started to appear.
Any assistance would be appreciated. Thank you!
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It may not be a memory issue, but it certainly could be a handle leak issue. It sounds like you're running the handle pool dry because you're not freeing resources properly, like Bitmaps, Pens, or other drawing objects.
Open Task Manager, Details tab, right-click the column header row and pick "Select columns". Turn on Handles and GDI Objects. Then go look at you app in the list. If the handles count just keeps climbing over time, you're not releasing objects properly.
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You may be right, but how common is it is to address "bitmaps, pens or other drawing objects" directly when you are running dotNet? Usually, that means C# or -as it looks like here - VB, with its GC. Usually it also means UI tools at a higher level, such as WPF.
It is still possible you have (functionally obsolete, but still valid) pointers to a large number of objects so that they can't be GCed, and these objects hold handles so that they can't be GCed. It could still be a handle leak issue, but the fundamental problem may lie in (say) C# objects not being made GCable - which is generally done by removing the last reference (i.e. pointer) to them, not by any explicit freeing operation.
In C#, you can use 'using' to hint the GC that it may free an object, but this is just a hint to reduce memory load. The GC should be running a GC cycle when memory gets low without such hints. I never worked in VB, and don't know if it has anything similar to 'using'.
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It's actual quite easy. For example, if you create a Bitmap object, you're just creating a wrapper around an unmanaged GDI object with a handle associated with it. Failing to Dispose the Bitmap properly and letting the Bitmap go out of scope will allow the GC to collect the wrapper object, and call the Dispose method on it, but not in a deterministic manner, meaning you have no idea when the handle will be released. This can result in you piling up handles waiting to be released and exhausting the handle pool before the GC can get around to freeing the Bitmap objects.
The same goes for all GDI related objects, files, and anything else being backed by unmanaged Windows resources.
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Possible? Sure. Common? ???
Ordinarily, dotNet objects are managed. Is is possible, through System.Runtime.InteropServices to call unmanaged code, and obtain pointers to unmanaged data objects. I don't think very many dotNet programmers will do that in cases where there is a managed alternative.
Re. Dispose: Sure, you do not know exactly when GC will come in and release the memory / handles occupied. But if resources run low, the GC will attempt to release non-referable resources; it will not just sit down and wait for the system to crash, the way you seem to suggest.
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trønderen wrote: Ordinarily, dotNet objects are managed
Yup. The reference is, but things like handles aren't. A lot of the runtime is a wrapper around the existing libraries.
Means one cannot rely on the GC to close those neatly if there's no dispose called.
Bastard Programmer from Hell 
"If you just follow the bacon Eddy, wherever it leads you, then you won't have to think about politics." -- Some Bell.
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A trick that I use is to wrap the objects I use into common classes so that I use them and free them up as soon as possible. The classes all have a Draw method and, in the Draw, I acquire the resource, paint it to the screen, and then release the resource immediately. The code I use to draw the objects doesn't need a Dispose method because the underlying object is disposed as soon as it is finished with.
I find that this really helps me keep track of my allocations.
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trønderen wrote: Possible? Sure. Common? ???
You'd be amazed at how many people don't know this stuff.
trønderen wrote: Re. Dispose: Sure, you do not know exactly when GC will come in and release the memory / handles occupied. But if resources run low, the GC will attempt to release non-referable resources;
If memory runs low, the GC will jump in and execute a collect. The GC doesn't look at the handle pool at all to determine if it should run or not. If your code is leaking handles like crazy, but memory is not being stressed at all, the GC will not collect.
Yes, I've seen it happen myself, with a service that Dell wrote, back in the day.
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