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copied!<p>When executing the ACE/Jet RND function against a new connection the same seed value is used each time. When using MS Access you are using the same connection each time, which explains why you get a different value each time.</p> <p>Consider these VBA examples: the first uses a new connection on each iteration:</p> <pre><code>Sub TestDiff() Dim con As Object Set con = CreateObject("ADODB.Connection") With con .ConnectionString = _ "Provider=MSDataShape;Data " & _ "Provider=Microsoft.ACE.OLEDB.12.0;" & _ "Data Source=C:\Tempo\Test_Access2007.accdb" .CursorLocation = 3 Dim i As Long For i = 0 To 2 .Open Debug.Print .Execute("SELECT RND FROM OneRowTable;")(0) .Close Next End With End Sub </code></pre> <p>Output:</p> <pre><code> 0.705547511577606 0.705547511577606 0.705547511577606 </code></pre> <p>Note the same value each time.</p> <p>The second example uses the same connection on each iteration (the .Open and .Close statements are relocated outside the loop):</p> <pre><code>Sub TestSame() Dim con As Object Set con = CreateObject("ADODB.Connection") With con .ConnectionString = _ "Provider=MSDataShape;Data " & _ "Provider=Microsoft.ACE.OLEDB.12.0;" & _ "Data Source=C:\Tempo\Test_Access2007.accdb" .CursorLocation = 3 .Open Dim i As Long For i = 0 To 2 Debug.Print .Execute("SELECT RND FROM OneRowTable;")(0) Next .Close End With End Sub </code></pre> <p>Output:</p> <pre><code> 0.705547511577606 0.533424019813538 0.579518616199493 </code></pre> <p>Note different values each time.</p> <p>In VBA code you can use the Randomize keyword to seed the Rnd() function but I don't think this can be done in ACE/Jet. One workaround is to use the least significant decimal portion of the ACE/Jet the NOW() niladic function e.g. something like:</p> <pre><code>SELECT CDBL(NOW()) - ROUND(CDBL(NOW()), 4) FROM OneRowTable </code></pre>

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