Databases
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    <p>You should use <code>ROW_NUMBER</code> to partition the huge resultset into smaller chunks. Then you could report progress on every chunk. Therefore you could use a <code>BackGroundWorker</code> to update a <code>Label</code> and/or a <code>ProgressBar</code>. To determine the size of each group you can select the total-rowcount first. Use this as divisor for the the chunksize (1000 in the following sample):</p> <p>Here is a working approach that fills a <code>DataTable</code> and select only small groups from the toal result using <code>LINQ</code>:</p> <p>On button-click start the <code>BackGroundWorker</code>:</p> <pre><code>Private Sub SomeButton_Click(sender As System.Object, e As System.EventArgs) Handles Button2.Click Me.BackgroundWorker1.RunWorkerAsync() End Sub </code></pre> <p>Handle the <code>DoWork</code> event to load the data:</p> <pre><code>Private Sub BackgroundWorker1_DoWork(sender As Object, e As System.ComponentModel.DoWorkEventArgs) Handles BackgroundWorker1.DoWork Dim tblData As New DataTable() Dim totalCount = 0 Dim chunkSize As Int32 = 1000 Dim countSQL = "SELECT COUNT(*) FROM dbo.tabData" Dim dataSql = "WITH CTE AS(SELECT d.*, rn=ROW_NUMBER()OVER(ORDER BY d.idData) FROM dbo.tabData d) SELECT * FROM CTE WHERE RN BETWEEN @RowStart AND @RowEnd;" Using con As New SqlConnection(My.Settings.ConnectionString) Using cmdCount = New SqlCommand(countSQL, con) con.Open() totalCount = DirectCast(cmdCount.ExecuteScalar, Integer) End Using Dim chunks = Enumerable.Range(0, totalCount). GroupBy(Function(i) i \ chunkSize). Select(Function(grp, index) New With { .RowStart = grp.Min() + 1, .RowEnd = grp.Max() + 1, .GroupNum = index + 1 }) For Each chunk In chunks Using cmdData = New SqlCommand(dataSql, con) cmdData.Parameters.AddWithValue("@RowStart", chunk.RowStart) cmdData.Parameters.AddWithValue("@RowEnd", chunk.RowEnd) Using da = New SqlDataAdapter(cmdData) da.Fill(tblData) BackgroundWorker1.ReportProgress(Math.Ceiling(chunk.GroupNum * chunkSize / totalCount)) End Using End Using Next BackgroundWorker1.ReportProgress(100) ' all data loaded ' End Using End Sub </code></pre> <p>Update the label and/or the <code>ProgressBar</code> on every chunk and finally:</p> <pre><code>Private Sub BackgroundWorker1_ProgressChanged(sender As Object, e As System.ComponentModel.ProgressChangedEventArgs) Handles BackgroundWorker1.ProgressChanged Me.ProgressLabel.Text = e.ProgressPercentage &amp; " Percent loaded" Me.ProgressBar1.Value = e.ProgressPercentage End Sub Private Sub BackgroundWorker1_RunWorkerCompleted(sender As Object, e As System.ComponentModel.RunWorkerCompletedEventArgs) Handles BackgroundWorker1.RunWorkerCompleted Me.ProgressLabel.Text = "100 Percent loaded. Finished." End Sub </code></pre>
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    1. POLoading a very large table from mssql to vb.net memory
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    1. USTim Schmelter
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    1. VO
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      1. VTUpMod
    1. COthanks alot, this is much better then what i came up with myself, i was doing soo many methodes :)
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      1. USDroa
    2. COi seem to have some problems loading the sql.. it takes about 5 minutes for each 1000 rows, i guess the code is too heavy for all thouse rows :(
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      1. USDroa
    3. CO@Droa: What column are you using for ordering, the PK-column? I have tested the code above with a table that has 15 Million records until the `DataTable` contained 1Million rows and that took 5 minutes.
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Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

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