david
2a98435b14
git-svn-id: https://192.168.0.254/svn/Componentes.Terceros.RemObjects@68 b6239004-a887-0f4b-9937-50029ccdca16
39 lines
1.6 KiB
HTML
39 lines
1.6 KiB
HTML
<html>
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<head>
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<link rel="stylesheet" type="text/css" href="..\styles.css">
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</head>
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<body>
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<img src="..\..\da.png" alt="" align="right">
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<!-------------------------------------------------------------------------->
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<p class="h1">Reduced Delta Sample</p>
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<p>
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This sample shows how to use <b>Reduced Deltas</b> to save bandwidth when applying changes to the server,
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where rows may contain potentially large but unchanged data.
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With <b>Reduced Delta</b> on, Data Abstract will only submit the changed field of a particular row to the server,
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rather than sending all fields with <b>Reduced Delta</b> off.
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</p>
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<p class="h2">Examine the code</p>
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<p>See the <b>TClientForm.btUpdateClick</b> event handler to see how the dataset is updated. Note how the Reduced Delta feature can be
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turned on or off according to the checkbox.</p>
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<p class="h2">Getting started</p>
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<ul>
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<li>Run the Sample Server.</li>
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<li>Run the Reduced Delta Sample.</li>
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<li>Try to fill DataSet.</li>
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<li>Try to change some records.</li>
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<li>Apply changes to the server, using the Update button.</li>
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<li>Examine the server log to see the command used on the server side to apply changes (it will contain only changed fields).</li>
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<li>Turn off the Reduced Delta feature using the radio button.</li>
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<li>Change some records and apply the changes to the server again.</li>
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<li>
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Examine the server log to see that when the Reduced Delta feature is turned off, all table fields are considered as changed.<br/>
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In this case we have used much more network traffic from client to server than what is normally passed.
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</li>
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</ul>
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</body>
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</html> |