doc-exports/docs/dws/dev/dws_06_0258.html
Lu, Huayi e6fa411af0 DWS DEV 830.201 version
Reviewed-by: Pruthi, Vineet <vineet.pruthi@t-systems.com>
Co-authored-by: Lu, Huayi <luhuayi@huawei.com>
Co-committed-by: Lu, Huayi <luhuayi@huawei.com>
2024-05-16 07:24:04 +00:00

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<a name="EN-US_TOPIC_0000001188110556"></a><a name="EN-US_TOPIC_0000001188110556"></a>
<h1 class="topictitle1">CHECKPOINT</h1>
<div id="body8662426"><div class="section" id="EN-US_TOPIC_0000001188110556__s917a3789243a44fe90ba8fecd69c2fb1"><h4 class="sectiontitle">Function</h4><p id="EN-US_TOPIC_0000001188110556__af9327feb7959426dace331755a30dea1">A checkpoint is a point in the transaction log sequence at which all data files have been updated to reflect the information in the log. All data files will be flushed to a disk.</p>
<p id="EN-US_TOPIC_0000001188110556__aec90fc6e6d8047ef9560e9af15ea26de"><strong id="EN-US_TOPIC_0000001188110556__b59233592115054">CHECKPOINT</strong> forces a transaction log checkpoint. By default, WALs periodically specify checkpoints in a transaction log. You may use <strong id="EN-US_TOPIC_0000001188110556__b63340282115054">gs_guc</strong> to specify run-time parameters <strong id="EN-US_TOPIC_0000001188110556__b33191629115054">checkpoint_segments</strong> and <strong id="EN-US_TOPIC_0000001188110556__b30289211115054">checkpoint_timeout</strong> to adjust the atomized checkpoint intervals.</p>
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<div class="section" id="EN-US_TOPIC_0000001188110556__sc71f019b5f904cf7829d18723a4c1fef"><h4 class="sectiontitle">Precautions</h4><ul id="EN-US_TOPIC_0000001188110556__ul1191111547244"><li id="EN-US_TOPIC_0000001188110556__li19912145413245">Only a system administrator has the permission to call <strong id="EN-US_TOPIC_0000001188110556__b116857232318">CHECKPOINT</strong>.</li><li id="EN-US_TOPIC_0000001188110556__li1272935712410"><strong id="EN-US_TOPIC_0000001188110556__b9670205993410">CHECKPOINT</strong> forces an immediate checkpoint when the related command is issued, without waiting for a regular checkpoint scheduled by the system.</li></ul>
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<div class="section" id="EN-US_TOPIC_0000001188110556__s5e5542d609234c11a660b757189a8c01"><h4 class="sectiontitle">Syntax</h4><div class="codecoloring" codetype="Sql" id="EN-US_TOPIC_0000001188110556__s9e9f754dee844e8d964a97c193800020"><div class="highlight"><table class="highlighttable"><tr><td class="linenos"><div class="linenodiv"><pre><span class="normal">1</span></pre></div></td><td class="code"><div><pre><span></span><span class="k">CHECKPOINT</span><span class="p">;</span>
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<div class="section" id="EN-US_TOPIC_0000001188110556__sbdf9ed2bfd134fa088b66414c1f15552"><h4 class="sectiontitle">Parameter Description</h4><p id="EN-US_TOPIC_0000001188110556__a2e73be8b0a23431ebe78d621b5408353">None</p>
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<div class="section" id="EN-US_TOPIC_0000001188110556__section15928164912119"><h4 class="sectiontitle">Examples</h4><p id="EN-US_TOPIC_0000001188110556__p17773524167">Set a checkpoint:</p>
<div class="codecoloring" codetype="Sql" id="EN-US_TOPIC_0000001188110556__screen1992894915211"><div class="highlight"><table class="highlighttable"><tr><td class="linenos"><div class="linenodiv"><pre><span class="normal">1</span></pre></div></td><td class="code"><div><pre><span></span><span class="k">CHECKPOINT</span><span class="p">;</span>
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<div class="parentlink"><strong>Parent topic:</strong> <a href="dws_06_0254.html">TCL Syntax</a></div>
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